1997 Lincoln Town Car - can I swap using a later model Town Car 4.6L engine and computer?

Yes, any of those would work, but you will still need to to reflash engine computer when done. Your older transmission won't work with newer engines, mainly due to torque ratings, shift points, electronic vs vacuum, etc., so either swap out entire drive train or stick to an older drive train (circa 97-98). You also want to know the differential gear ratio of the donor car, if it matches yours (good), if not, you'll need to know what it is for programming ecu. BTW, you should check with all the local auto salvage and parts dismantlers, I see used and refurbished heads for about 200 a pop, entire engines for 600 w/ 6 month warranties. Places online are much higher, but I'm talking LOCAL salvage yards. Go see them in person and start asking around.

If you stick withe the same yr n specs just drop the engine n drive. Most towns are in salvage due to wrecks or abandoned. Also try to get 1 that you can hear it run first

I did a 2003 crown Victoria engine into a 97 if you swap the intakes everything works out fine.