you can get h23/h22 mounts for 3rd gens not to mention custom mounts always work as long as you know someone who's can make em any engine is techincally feasable you could put a f20c1 in a 3rd gen and convert to rear wheel if you had the time and the money it all depends on what you want to do and how much you want to spend if you just looking for a quick fix for something to toy around with do the fi swap if your looking for something to be a rocket try the h22 or b16b or a b18c6 with custom mounts hell go absoulty nuts take out the rear seats and put a c32a (nsx motor) and build a engine bay around it now that would be nuts