The past two years I haven't been able to find anyone willing to weld in small floor patches for fear of warping. I don't know how to weld, but I did use panel adhesive on another car with success and it's holding strong 6 years in. So I got some 3M panel adhesive, a piece of steel, and some tin snips and fixed the floor myself. The underside is totally por-15'd, waxed, etc, so I just needed to take care of the top. Were this a show car or being painted, I would want the patches flat- but the bed liner and goal of daily, year round use means this will work just fine.
Cut my patches, hammered them to shape, glued them in and clamped them down for the night
Sanded them down, applied Chassis Saver
Then rolled on the bed liner
Really happy with the result, and should last a good long time.