Civic EG

I have a b16 trans in my 92 eg hatch. A friend put new Carbon syncros in. Now I can't ingauge 3rd and 4th has a little scratch. I drove it once. My question is are all b16 tranny internals interchangeable? Example: Jdm to USDM ? I see blown cases everywhere and wonder if I found a good set of shafts ( main & counter) if I could swap them out. Thanks for all information and help again!

If you can't shift into 3rd something is wrong and that should have been obvious/addressed prior to putting it back together. Do you have anyone you trust to assemble it correctly?

I'm not sure if I have a jdm or USDM. I just want to know if their interchangeable. And I don't think I'll use the same guy.