[dinosoar]

I may be wrong but I believe that the fifth gear ratio may be a bit shorter in some sherpa boxes.
However this is dead easy to swap if you have a donor box as fifth is housed in the alloy bit at the back and the gears can be swapped without any special tooling or upsetting any bearing settings.
First may also be a bit shorter.
I think most sherpa boxes were D Spec and therefore have the larger shafts and bearings. Synchros are bound to have had a hard life though. They can be deglased by giving the offnedin gear a good hard shove whilst engine is running, foot hard on brake without the clutch pressed.

Andy