New to Corollas, and need some help

#1
So I bought 79 Corolla a while back and I need a new pilot and throw out bearing and possibly a new transmission. I was wondering if anyone had any insight on how to perform a smooth transmission drop and where to find the parts I am looking for. Also if it turns out that I do need a new transmission I am curious if there are other transmissions besides the T-40 and T-50 that will fit. Any advice would be great!
 
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