If the new boss is the splined bit off the BSA footrest hanger, they're on long back order with a depressing note against them!
Martin, your splines look good, take care of them. That long stud is often difficult to get out as it's a pretty snug fit to start with (although if it's binding that can help with tightening - and loosening! - the footrest nuts). Drawing it out using one of the nuts and a variety of spacers/bigger nuts/sockets/washers (as Mick suggests) is my favoured method.
If the swing-arm bushes aren't noticeably soft/loose consider leaving them alone and not taking the spindle out. It makes painting more difficult but you avoid a lot of other pain! (When I built my s/arm bike back in 1980-something the spindle wouldn't come out, 40-odd years and maybe 40,000 miles later it's still OK....)(Although every time I say that I hope it's not a case of 'famous last words'!)
SG


