My donor was a 1990 sierra 2.0dohc, I've mated the mt75 to a 2.0 blacktop so will my donors starter motor be ok??

Yes

Yes, using the black top sump ? you will have to hack lots of the sump. Offer it up and all will become clear.

[Edited on 26/4/11 by big_wasa]

brilliant Im using the scholar sump so no hacking