I've got my TS properly back on the road & driven about 1500 klm since some work in the ACT.
The mechanic in Canberra was reluctant to do a gearbox rebuild to address the 1-2 syncro problem, & instead recommended tightening the linkage joins + using Redline superlight shockproof gear oil. It's fully synthetic, costs a bomb, but works a treat & much cheaper than a gearbox rebuild. Stoked, it's a far better gearchange now.
Great result from this oil, better than any other I have used in the last 12 years on TS & 3L 75's, and that includes many of those above.
Recommend it very highly.