There were several different models of the GTI-R sold to the general public, identifiable by the model number found on the VIN plate located on the firewall in the engine bay.

GTI-RA: Model number EBYNRVFN14T******* (aka RA / Alpha / Road / Luxury).
This was the normal road car, which came standard with air conditioning, power windows and mirrors, and ABS.
Roughly halfway through the production (August 1992), Nissan made a range of cosmetic changes to the interior of the RA model (mostly replacing trim that was unique to the GTI-R with trim that was common to other models in the N14 range).
Although not advertised or branded as such, they were extensive enough (around 10 items) to be noticeable as a different phase or series, and are defined by chassis numbers RNN14-100000 and above.
They were priced at ¥2,270,000.

GTI-RB: Model number EBYNRRFN14T******* (aka RB / Base / Beta / Rally / Homologation).
The homologated model was stripped-down as a base for motorsport use (Group N rallying in particular).
It had the luxury trimmings such as air conditioning, power windows, and ABS removed as standard, and the simple interior trim from the base model N14 which reduced the curb weight by 30 kg (66 lb) to  1,190 kg (2,624 lb).
A close-ratio gearbox was a production model option, some of the RA items could be optioned (such as rear wiper and air conditioning), and many Nismo parts were available at time of order (such as mechanical limited slip differentials and upgraded suspension).
Those that were ordered with Nismo parts not suitable for dealer install were sent to Autech for factory installation.
The only external visual difference to the RA is non-colour-coded side mirrors.

Sunny GTI-R: Model number EBYNL*N14*******.
Sunny was the badge used for the European-delivered GTI-R, which has the different chassis number of EGNN14.
The engine and mechanicals are the same as the Pulsar GTI-R but the power and torque specifications (220 PS / 162 kW and 267 Nm / 197 lb·ft) are slightly less due to the ECU having different fuel and ignition maps to compensate for the lower octane fuel available in those regions.
There was no RB variant offered, but they were available in both LHD and RHD configuration.
The only obvious external physical difference to the Pulsar is the rear number plate surround (to accommodate wider European plates).
The interior varied from the RA Pulsar with some of the more basic trim from the RB model and different scaling on the gauges.

Other versions:
Nismo: Nismo offered a "Complete Car" version based on the RB model featuring many of the Nismo rally options (such as suspension, limited slip differentials, roll cage and foot rests), and strengthening plates spot welded to the strut towers.
A total of 21 were produced, with an individually numbered Nismo VIN plate on the firewall.
At least one was used by Nissan/Nismo as a promotional vehicle, the others were ordered by private buyers.
They were priced at ¥3,140,000.

Group A: The works rally cars were built and used for the WRC by Nissan Motorsports Europe (NME), they were not available to the general public.
After the GTI-R program was shut down, the cars were sold to private buyers, predominately in Europe, where some made their way into rallycross events.
Tony Bardy regularly competed in UK rallies using one until 2015.
Nissan has the 1991 Acropolis rally and the 1992 RAC rally entry vehicles on display at the Nissan Heritage Collection in Japan.
There were several different models of the GTI-R sold to the general public, identifiable by the model number found on the VIN plate located on the firewall in the engine bay.
GTI-RA: Model number EBYNRVFN14T******* (aka RA / Alpha / Road / Luxury). This was the normal road car, which came standard with air conditioning, power windows and mirrors, and ABS. Roughly halfway through the production (August 1992), Nissan made a range of cosmetic changes to the interior of the RA model (mostly replacing trim that was unique to the GTI-R with trim that was common to other models in the N14 range). Although not advertised or branded as such, they were extensive enough (around 10 items) to be noticeable as a different phase or series, and are defined by chassis numbers RNN14-100000 and above. They were priced at ¥2,270,000.
GTI-RB: Model number EBYNRRFN14T******* (aka RB / Base / Beta / Rally / Homologation). The homologated model was stripped-down as a base for motorsport use (Group N rallying in particular). It had the luxury trimmings such as air conditioning, power windows, and ABS removed as standard, and the simple interior trim from the base model N14 which reduced the curb weight by 30 kg (66 lb) to  1,190 kg (2,624 lb). A close-ratio gearbox was a production model option, some of the RA items could be optioned (such as rear wiper and air conditioning), and many Nismo parts were available at time of order (such as mechanical limited slip differentials and upgraded suspension). Those that were ordered with Nismo parts not suitable for dealer install were sent to Autech for factory installation. The only external visual difference to the RA is non-colour-coded side mirrors.
Sunny GTI-R: Model number EBYNL*N14*******. Sunny was the badge used for the European-delivered GTI-R, which has the different chassis number of EGNN14. The engine and mechanicals are the same as the Pulsar GTI-R but the power and torque specifications (220 PS / 162 kW and 267 Nm / 197 lb·ft) are slightly less due to the ECU having different fuel and ignition maps to compensate for the lower octane fuel available in those regions. There was no RB variant offered, but they were available in both LHD and RHD configuration. The only obvious external physical difference to the Pulsar is the rear number plate surround (to accommodate wider European plates). The interior varied from the RA Pulsar with some of the more basic trim from the RB model and different scaling on the gauges.
Other versions:
Nismo: Nismo offered a "Complete Car" version based on the RB model featuring many of the Nismo rally options (such as suspension, limited slip differentials, roll cage and foot rests), and strengthening plates spot welded to the strut towers. A total of 21 were produced, with an individually numbered Nismo VIN plate on the firewall. At least one was used by Nissan/Nismo as a promotional vehicle, the others were ordered by private buyers. They were priced at ¥3,140,000.
Group A: The works rally cars were built and used for the WRC by Nissan Motorsports Europe (NME), they were not available to the general public. After the GTI-R program was shut down, the cars were sold to private buyers, predominately in Europe, where some made their way into rallycross events. Tony Bardy regularly competed in UK rallies using one until 2015. Nissan has the 1991 Acropolis rally and the 1992 RAC rally entry vehicles on display at the Nissan Heritage Collection in Japan.
Nissan Pulsar