Re: 156 back brakes
Well, that was fun. Can understand that it helps the self adjust, but don't really see what was wrong with the old system - oh, just got it (that light bulb moment) it's for the handbrake innit?! Doh, of course.
Anyway, for those without either a windback tool or a tool shop within walking distance, this is how you do it.
Get a 10" sliding woodworking G clamp (with the ball/socket articulating clamp piece on the thread) and unwind the thread completely. Put the rigid end on the handbrake lever bolt and the pad on the caliper piston. Slide the bar up and tighten. Use above-mentioned padded pipe wrench to tighten half a turn on the piston. Retighten clamp, 'nother turn on the piston, retighten etc...
First one took ten minutes, second one less than two minutes.
Thanks all for your input, much appreciated.
The artful bodger.