Thank you for that link Fazersharp, sobering thought! I took the arm off this afternoon and offered up the original (Fazer 600), same problem it was out of line and would only be forced on which would put a lateral force on the swing arm lug. I've refitted the TRX arm with an alloy spacer between the "jaws" of the arm, a longer bolt and located it outside the flange on the caliper bracket. I'm happy that this will do the trick. Thanks again for your help. I'm trying to post some pics to show what I've done.