I understand. For sure, internal is more convenient. Swapping displays is possible, if you're careful. Display cable and connector are fragile. I don't know the part number. You could ask [NAME]-Cares, send Private Message with your question. Whenever touching components or working inside a computer, wear a grounded wrist strap, also called anti-static wrist strap, ESD wrist strap, or ground bracelet. It's a cheap and sensible precaution. Rest the laptop on an anti-static mat or at least a reasonable alternative such as corrugated cardboard.
So I got a brand new 7770 and noticed it has a sim card slot in the back. Further digging and I need a wwan card but it needs to be wired during installation. I removed the heat sink assembly to find that the wire mentioned in the manual directions does not exist. After some chat support length, I was told the antenna is built into the screen... The link below shows this "WLAN bracket" and antennas. I dont have the antennas and mine looks like the WLAN bracket but not exactly like it... Does anyone know how and what I need to install a working cellular connection to this laptop? I could probably buy an external USB one but then I have to lug it around with the laptop...   [URL] [URL]
DELL Precision 7770 WWAN + Antenna Wiring