It fits easily now, on the main bracket I use 2 M8 bolts instead of studs and nuts,I also use a M6 bolt on the tailpipe. Allen studs with nuts might be a future option, at the present,I have perfect threads on the cranckcase. I fit the exhaust in the following order, first I tighten the stub nuts having a copper gasket fitted between the stub and the cylinder, then I mate the main exhaust body on the stub joint, the exhaust 'u-bend' was hitting/fouling on the cowling (I use a 1mm head gasket but the clearance was a joke) I had to bend the front of the cowling a lot,I don't know if it can be seen from this photo. After doing this, I managed to slide it on the joint a little,BUT it started fouling on the other side, the only way to make it fit and slide it all the way in,was to make this cut. This is how it looks from underneath My advice to you,in order to avoid future drama,is to check the clearance with the cowl fitted,.