Just done a Virago tank with products from Caswell europe The tank had 15 year old stinking, varnished fuel in it and had rusted from condensation I think. I cleaned the tank with acetone and loose nuts and bolts, but do not go too big with them as shaking them vigorously ended in knocking small paint chips off the outside of the tank, small lengths of bicycle chain sliding around inside was best, a few rinses with acetone then hot soapy water, the Cawells water based Comscale rust remover amazing stuff disolves the rust, a few days drying then their epoxy resin poured in and rolled around they state half the measure does a 3 gall tank mine was under 4 gall and I used all the mix on one hit and it was all used, the interior finished like glass any little crumbs which I could'nt flush out were encased in the resin, about 70 odd quid for the bits, and I did'nt bother wrapping the tank or anything like they recommend, I used duct tape to seal outlets and was just careful with what dripped or ran out and wiped it up immedately