Hi Roger, I see you have a F133. I've had a lot of trouble with the outside rear strap positons ,middle and forward holes on my F133 Wood. The rear outside strap is not parallel with the centre line making it very difficult to get into. Coupled with narrow straps ...a nightmare. Have you had this problem? Where do you run your rear straps?
Oddly the front strap is not narrow, and set fine.