It would help to read the pinned note at the top about revised shift forks.
The person that knows this trans better than anyone alive is Terry Haines. Do a little searching and you should be able to find out how to contact him.
Also do a search on fluids for this trans. The right fluid may make the 3rd gear synchro problem tolerable without the expense of an overhaul. I would certainly recommend changing the fluid over to ATF+3 before doing a tear-down. If the improvement is significant, then you may want to try one of the synthetics that you can find info about from past posts. I have the Ford honey colored synthetic MTX fluid in mine at the moment with added Ford friction modifier and I have all but forgotten that there is a 3rd gear synchro problem.
