13b transmission into a 12a?
 

My transmission is starting to go out on my 85 GSL. Rather then to have it rebuilt I thought that it would be a better idea to install a GSL-SE one instead. My question is - besides having to change out the flywheel, what else do I have to worry about in terms of installing into a 12a engine? Also would this give the car a little bit more power or is this transmission pretty much the same as the 12a one?