There is a few interesting points to watch out for on the gearbox particulary if you have the gearbox cabin mounted covers removed you should consider...
Check the remote gear selector rubbers they often harden and perish and make gear selection more difficult ...replace with poly bushes.
Check the gear selector 'cup' for damage or fatigue as the mounting tab breaks off...
See photos below, I do have a supplier and part no for the poly bushes
Untitled by
Robert & Ali Davies, on Flickr
IMG_1358 by
Robert & Ali Davies, on Flickr
IMG_1363 by
Robert & Ali Davies, on Flickr
IMG_1359 by
Robert & Ali Davies, on Flickr