Thanks for that J-Tac. I can live with 0mm offset, I shall be looking at new shoes and rims in the new year.
Just done the valve clearances using the manual I downloaded here and using Solarmans advice on backing off quarter turn instead of feeler blades. Also removed small filter from banjo bolt on fuel pump. Runs lovely now, best £10 I've spent in a while on membership, half the price of a Haynes manual!
Many thanks to everyone