I have removed the circlip from around the transmission's input shaft
(took it out of its groove and moved it aft) but I can't get the sleeve
to budge.  I tried some gentle taps using a length of wood and a mallet
but I didn't get too vigorous as I didn't want to damage anything.

Anyone have some tips, tricks, or words of encouragement?

Thanks,

Mike
Houlton, Maine
'85 GL Westy 4 speed