1989 Ford Tempo FUEL PUMP QUESTION

It won't 2 different P/N

If you mean it's a shoe in fit then not likely?Generally what you want to match is fuel pressure?I have used different pumps to run different cars before.A little bit of custom fitting was required like wire connectors.I put a chevy lumina van pump in a 87 cavalier a couple years ago and it's still runs fine. That was a high pressure pump used on v6's.I think tempo uses a low pressure pump. May depend on fuel sytem. Throttle body or multi port. If you put a high pressure pump on a low pressure system maybe it would just blow the extra pressure back to tank?All systems have pressure/return regulators.I have also accessed tempo pump by cutting metal from inside car under back seat(middle hump)and then making tin screw on cover to replace.