[vettestr]

Paul,
Grab anything from a drip pan to a piece of sheet-metal. Apply a couple of coats of car wax to the entire area, wiping clean between coats. Apply resin to area then wet out mat right over the top keeping it very resin rich or heavy. This is because the resin over a waxed area will try to fish eye but the wetted mat will help stop that. Mix the resin a little hot so you do not have to babysit from fisheyes very long.

After first layer has kicked or set up hit area with like 40 grit paper just to scuff up well and apply additional layers at normal resin to mat ratio until desired thickness. Let finished product sit on metal surface overnight or put out in sun for a while. Depending on type - quality of resin it will shrink and curl if you remove to soon. An air blow gun or a scrapper under a corner will remove from sheet metal. Applying resin and mat against metal will give a smooth surface to make door out of for your needs. Have fun.