91 tranny in a 90 swap

[gsx_tuner]

Does anyone know where I can find any literature or faq's or just any information at all in swapping a 91 tranny into a 90 awd? There are subtle differences between the two, but I heard it can be done with minor alterations. If anyone could post a link to any info that would be great. Here is the problem for those who care, tranny went out in my friends 90. We bought a 91 tranny. The x-fer case fits fine. We put a new act 2600 clutch in there, turned the flywheel (first time to be turned) and a new throw-out bearing. The car grinds when you drive it. As soon as you press in the clutch the grinding goes away. We took all wheels off the ground, a drove it, and it still grinded. If anyone has any idea, I am sure the simplest idea would work, at this point we will try anything. So please respond with whatever you think, no matter how insignifigant you think it might be. I thank you in advance for any responses posted. -Ross

 

[1stGENracer]

Did you guys replace the throw out bearing also? Bad throw out bearings can make some nasty noises.