I freeformed it with sheetmetal and welded then used bondo-glas, (the stuff with fiberglass in it and resin gell) and then Body filler. A few nips and tucks shall we say.
My shoulders gave up on sanding so I stopped and painted.
(one of those things that why Am I making Everything perfect and I will be covering it with a tool box and tube anyway?)
Kind of a "truggy" look I am going for. that and I will be running 35's this year too.