Dear all,
Thanks for the comments on the brakes.
I have now have both calipers apart, all seal removed and the pistons out. The calipers have been off the bike for years (perhaps even decades) and there is no fluid in them. I found an article in Classic bike where they removed rusty pistons by drilling holes in them, using a tap and then a bolt to push them out. Works a treat although the pistons are hard to drill and they were rusted to hell. It seems that Tricor (and TMS) do a complete caiper seal kit and stainless pistons and so its only money... (if I dont spend it the wife will!).
Thanks again