Whats involved in using a 90 awd tranny on a 91 car???

[90 GSX]

Say I have the above scenario... I can either get a tranny, or and tranny+t-case from a 1990 locally for a good price. I need it to replace the cracked bellhousing in my 91 tsi..

1 - Can I swap only the bellhousing and use the same tranny? A subsequent question would be, is the bellhousing separate from the transmission?
2 - Is the tranny a direct swap? I have heard the t-case spline count is different. If so, what parts are interchangeable?
3 - If I'm completely clueless so far, what do I need to do to make it work?

Thanks in advance. Don't go too hard on me defiant haha.

 

[T5Kthrasher]

im in the same spot as the OP so bumping for some info

 

[90 GSX]

Bump it up.

 

[02BLUR]

Say I have the above scenario... I can either get a tranny, or and tranny+t-case from a 1990 locally for a good price. I need it to replace the cracked bellhousing in my 91 tsi..

1 - Can I swap only the bellhousing and use the same tranny? A subsequent question would be, is the bellhousing separate from the transmission?
2 - Is the tranny a direct swap? I have heard the t-case spline count is different. If so, what parts are interchangeable?
3 - If I'm completely clueless so far, what do I need to do to make it work?

Thanks in advance. Don't go too hard on me defiant haha.

As far as I remember, only the input to the xfer case is different. I think 90's have 22 teeth and 91's have 21.