So, it could be with a new brass fork for 3/4, needle bearing, front main bearing, general cleaning and careful reassembly, I could have a "decent" gearbox again? Unless the there's enough wear on the various teeth (as pictured) that it would require more bits and then not be worth it anymore? I'm surprised that the only symptom after this catastrophic failure was the inability to engage 4th. All other gears and shifting remained just fine. I drove it around like this for a little while, probably not more than 80 miles. If you think a 5th gear is needed, try living without 4th for a bit! Wonder how hard it is to get that 3/4th fork? Probably just as easy and same $$ to get another whole used box! Thanks again for the input! I'm learning lots and lots.
Interesting, 3/4 fork unavailable from Moss or VB.....
Oh, BTW I doubt it was a mistake on reassembly that caused it as the box hadn't been opened in 20 years, if even then. I would not be surprised that this is the original box and it was untouched until I tore into it. I think it was drained for engine pull, then never refilled, that it was run with no oil ever since (since 1987). 1995 miles on it since then, 95% short trips. Is it conceivable for an oiless box to hold up that long? Long time, precious little usage though.
BTW I've managed 5,000 miles in 2 summers, more than the previous 21 years.....as it was built for IMHO. Garage queens suck.