Thank you for that, my computer is still out of action and I have to use my phone which doesn't take good pictures. I am getting a lot of hassle from previous owner at the mo as I want the original exhaust for MOT time but it's not forthcoming! Anyway he did tell me he had to use a special thin angled screwdriver. This won't beat me!!!! (I still love my bike in pieces!!!!)

Just for info and clarification I have a 1WG head with 3TJ rubbers and carbs. I know without pictures it makes it hard because in all the pics I've seen, the cooling system pipework on back of cylinder block is 3TJ also which makes me wonder if it is possible I have a 3TJ block?