Last time I covered the welded patch with POR-15 Epoxy Putty. Today began with sanding it down. For starters I used my CP grinder, then switched to #50 paper on a sanding block. Tight spot, so it took longer than normal.
What this revealed was a low spot to the right (of the car) extending to the start of the vertical piece. I decided I had to fill this, too,but before that I had to patch a small hole with fiberglass and POR Patch. Too my surprise, my brand new tube had already kicked off. Well, I bought it a couple of months ago, I just opened it today. Still, that was a disappointment. What came out was really thick, but soft enough to work into the woven glass.
With the hole patched I opened up my new Epoxy Putty, which was still good, and filled in the low spot. Naturally I stuck my finger in the POR-15 and now have black finger tips.