Rivnuts for soft top hoop set?

Spring is here and time to swap the pickup cab for the soft top. Bolting the hoops has been a tedious process in the past, especially that one spot where it's almost impossible to get the nut on the bottom of the bolt because it's inside the bed rail.

I was thinking about using rivnuts to speed up the process. Anyone else done this? The bed rail + galv capping is thicker than regular sheetmetal, obviously. Any concerns there? Steel rivnuts + antisieze OK?

Tons of threads on the other site saying the Harbor Freight tool is sufficient. Anyone concur, or would you suggest something else? I don't mind spending money on a good tool, even if I won't use it more than a few times. My sanity is worth it. Tried the bolt and wrench method when I installed the side steps and it was a PITA I don't want to repeat.
IMO, measure the material thickness and make sure you get the right rivnuts. ex. M8 is avail for material upto 7.9mm thick. Good tools are always a good idea.