the 7 bolt motor is a 1994 Eagle Talon DSM motor, it will work on any turbo chassy with the original tranny 89-94. as long as the cas can be used and in 2G's, the cas is used with the wiring harness with the help of the 1G ina 2G wiring harness that splits it to the knock sensor harness and 2G cas harness.

if you want to put a 7-bolt 4g63 motor in your 91 you can do it, but seeing as how all 7-bolt motors crankwalk at one point, maintenance is key and oil is very important.