What's the best way to mount something heavy to the inside of the tailgate. I wouldn't think sheet metal screws would be best, because I would need so many. I've looked for nutserts at lowes, and they didn't have any. I guess I could try fastenal, but the ones near me won't break bags, and I don't need 1000 of them.

Has anyone mounted a subwoofer or tool box the sheet metal on the tailgate?

 

I would avoid mounting anything more than a shovel or camp axe back there. I have run around like an idiot trying to find the right hardware. Maybe order an $89 flux welder from harbor freight and make some mounting brackets

 

I've seen subwoofers that mount to the tailgate. How are those bolted on? My tire will be supported by the lod rear bumper, so weight on the hinge won't be a problem.