Thanks all, no one is intrusive all good ideas gratefully received (I am not sure what to do with bad ones????)
Today was trying to solve the clash elegantly. I thought the problem was the bolt head protruding beyond the face of the rear set. so how to get rid of the bolt head. A mushroom cap screw was considered but difficult to buy in that length also the hole in the rear set was drilled an odd size (slightly less than 7mm).
My solution was to tap the hole in the rear set 8mm and machine a piece of steel bar with an 8mm thread for the thickness of the rear set and turn it down to 6mm for 45mm and thread the last 10mm with a 6mm die.
It took a long time to make because the only bit of steel I had was 10mm diameter and my lathe will only cut steel about 006" per cut. Also all the calibrations on the lathe traverser and lengthways slide are imperial.
Anyway when I fitted it the brake pipe union still fouled the rear set so I will have to turn up some spacers similar to those in Dukedesmo's post.
free picture upload