Stuartie_c…I'm by no means an expert, but I am listed on the BC website as a coach and I've worked in various bike shops (a couple of years back now, mind) so I like to think I have a reasonable idea of what I'm doing.
Anyway, mostly the problem I have giving advice on here is that without actually seeing someone ride a bike it's not so easy to really diagnose the problem. That said, I live just on the south side of the Forth so if you like, I can, for once, RV with you somewhere and offer a few thoughts on your position/set up and hopefully help you find a less painful set-up!