The underside was prepped by stripping it back to the original primer using white spirit, any rust was then prepped using a grinder with a wire wheel attachment which got most of it off. The remaining bare metal/stubburn rust was treated using Kurust and then painted using Red Oxide Hammerite paint (The welds were coated in a thick rust prevention primer first). It all got at least two coats.

The underside will now have two coats of a black Hammerite paint before being stonechipped (As recommended by a local restoration place, they've qouted £35 to come out and stonechip it with a portable compressor not including materials). I will then probably go over it again with a last coat of black hammerite to make it nice and shiny