from there, i cant decide on a couple of immersion heaters or just kettle elements. imersion heaters would be best i think(bigger), but the hole would need to be huge to install them in the side of the keg, and i cant find a hole saw big enough.
turns out a friend is a sparkie, so i asked him about earthing the whole thing, i had concerns it had to be over the water line, but it doesn't. score!!
just need a wee bit of cash before i can convert it all though. too skint just now.