How is a part time research job (from a University) perceived in the academic job market? In a similar vein as the question How is a part-time degree (from a reputed institute) perceived in the academic job market?, what about holding a part time research job (Research Fellow)?

Currently, I work part time as a Research Fellow, part time High School Teacher, part time Programmer and part time Drone engineer - so, as a result, the amount of research output would be considerably lower than I would if full-time - a position I am aiming for in the near future.  I already have a PhD.

In my CV, it will be very clear that this is a part time position, due to the overlap of my professions - this is different to the part-time degree scenario in the linked question, in that I am already in academia. How valuable is a part time research job with respect to joining full time academia (or industry)?
Well, it's much better to have a part-time research position than no research position---or more accurately, it's much better to be doing some research than no research.

I assume from your question you are either looking for a tenure-track/permanent faculty position at a research school or a research-oriented postdoc.  If you want me to assess your chance of success, I can't accurately do that without knowing a lot about your situation---in most areas I know of, the job market isn't great now, but certainly some fields/geographic regions/types of positions are less competitive than others.

Basically, for a research-oriented position, you want to convince the people in charge of hiring that you're going to do great research and contribute a lot to the research group you're trying to be a part of.  Generally this is easier the more research you've done.  

However, if the amount and quality of research you've done is impressive for someone doing other work part-time, that will probably taken into account--which is maybe what you were really asking about.  For instance, if two candidates have comparable research and one had a heaving teaching load at the time and one had a light load, the one with the higher teaching load looks more impressive.  

But if your research output is considerably
less than the competition, it's harder but not impossible to be viewed as a top candidate.  Here outstanding references can help make up for this.  Also, this is probably not a much of an issue if you are looking for postdoc positions.