most often you should change the rear output bearing(because it needs to be pulled off and it takes a bit of force most of the time, i generally ream out the new bearings to be a slide on fit), 5th gear syncro and the 2nd gear syncro. 5th gear is the most common problem and most often the transmission doesn't need to be completely disassembled. most shops would charge about $250 to replace the output bearing and 5th gear syncro.

the input bearing is also a wise idea to replace as it takes most of the load and usually whines when it gets older.

 

I' overhauled the gearbox with new bearings and synchros and it is expensive. Try BNR. I recently bought 2 good trannys from him.

bnrsupercars.com

 

if you look up the 5th gear in the JDM parts catalog it lists a different one for 16" and 17" wheel cars, its even in english.

 

Wow! I'm impressed guys. A lot of knowledge here! Just go give everyone a run, called a couple of shops for rebuilds aren't cheap, if you guys know what I mean. Also called around for used trannys, ours roughly $400 differences. I'm still contemplating about the options.