Hi Stuart
There are 2 felts used on the gearbox
1/ push rod felt - quite small & often lost in time
Hard to find available to buy - mark at PES had a correctly shaped / formed batch made recently
2/ main shaft felt - this tapered felt fits into the outside of the 4th gear / sleeve gear where the main shaft protrudes - you will note a recess in the outer of sleeve gear where this is to be positioned