Philip I used the same universal type tube of auto body seam sealer on the cab belt of my 40. I have not painted it final color yet but after two coats of primer and sanding I like the look of it. One thing I did when applying it was to cut a nice small radius out of a plastic bottle and used it to smoothe out the sealer as I applied it. This left a good looking fillet to finish over. Hope it works for you.
Bob