Yep - off the legs.

I immediately screwed down tight the braid in the header and ensured a good connection, but didnt have time to go any further.
 Floating ground was my thought too - get a nip off all grounding wires inc lamps etc. I couldnt feel it at first cos the skin on my finger tips is pretty thick. Was only when my forearm touched the leg that i got bitten. Skin there is like a babies bum. LOL- gave me a start!