Ian,
Have you tried finding 3rd gear, with the adjusting plate loose, coming to a stop and
tightening the plate, and see if the rest of your shifts are accurate?

bob

So I come to all of you nice people and ask fit here's anything we're
missing, or if the answer is to continue trying to move the plate the lever
bearing rests in around. Anything is welcomed at this point, because it's
getting a little irritating that first occasionally turns up where reverse
should be, but never back where it belongs.

                          Thanks in advance,  Ian MacDonald