Be aware that the front mount (under the passenger side - where the timing chain is located) is different between the auto and 5-speed. My driver is a 2.5 with a 5-speed and I took the front mount off of another '87 that had a 2.5 with an auto and the mounts (and mounting holes) are different. The holes are about an 1/2 inch closer together. It doesn't make sense to me that they would be different - they are at the opposite end of the motor (away from the tranny).
Good luck. Jimmy
1987 Fiero coupe; Blue; 2.5L; 5-spd
1987 Firebird Formula; Blue; 5L; 5-spd