Mate
Don't try to take the top lettering plastic cap off as its stuck on with very old adhesive as the numbering and gear pattern will rub off, I tried this and messed it up. I have 2 spare gear knobs that I will be giving to Jack at royal steering wheels to do, not sure how he proposes to take it off or leather around the lettering.
I will update once mine are done
Regards
Indy