Decided last weekend that it was about time I serviced my EXUP valve.
After 2.5 hours stripping it down and getting the fecking bolts out I finally removed the external plate (that was all connected up to the cables and everything) and found there's no bloody valve in there.
Oh well, I've bought some stainless bolts for it today and I'm going to get a peice of 4mm thick stainless plate and make a blanking plate for it. That will do until (or If) I can get a valve off Ebay.