Anders, as this is one job that I have always felt was easy to sort I'd say that something is out kilter .On my primary side last year I had to weld the distance piece to footpeg due to wear on the splines . It is more of struggle to fit it but not by much just needed to be jiggled. Normally I'd simply feed through the long bolt having loosened my exhaust pipe (Siamese system so primary side is clear ) to allow access from that side push through until just seen in with the distance piece turning to get it to engage with the peg hole on the plate ,footpeg over the bottom rail and onto correct spline and then that bloody big nut ,not forgetting a shake proof washer and the jobs done. So if it's not working out like that check the bits . Has the footpeg been bent ,I've one that's a lovely shape , the splined distance piece, one is shorter, you haven't got 2 the same length have you? or could it be off another model, make ,some pre unit trumpets used something similar but a bit longer . I hope you don't think I'm stating the obvious but this job shouldn't this complicated. I hope you sort it quickly cos this type of thing is bloody infuriating , best of luck Bob.