Decided to strip my GP down yesterday and sort out the annoying drip from the crankcase gasket so armed with new stainless studs ,washers ,nylocs , gasket and clear silicone I set too only to realise the leak was coming from the brass level plug , not the fibre washer but the plug itself , come to the conclusion it must be either porous or have a split in it .
Thought I'd share with you in case anyone else has the same annoying drip .