Proper gauge sheet metal for repairs and flares

So I have a couple things I need sheet metal for and the stuff I have currently it way too thick for simple repairs or flares. I mocked up a bit of a frame for making flat flares so I'd love to kill two birds with one stone and use the same metal for that and my rusty floor fixes. I don't have a metal break so I'd be bending by hand. Would 16ga be thin enough to bend by hand but thick enough to patch some 6-8" holes in the floor? The holes just need to be filled so I can get undercoating on and hopefully some noise suppression on top as well.

I just took a sheet metal gauge to a chunk of '96 that I kept to patch my '90. The body panels and floor pans are 20 ga.

If you look at sheet metal tooling, most hobbyist grade equipment will have an 18 ga max capacity. Anything heavier and you get into spending cubic dollars.

I am thinking that 16 ga will take some effort to form by hand. If you can go with a lighter gauge material to put a skin on something, you have not lost any strength that is not already there.

Thanks. I've been using my 14ga in the rear to fix the rust above the shackles so I had something beefier to bolt the shackle boxes to but I have no desire to try to form that around the top of the wheel well where I just need to close up a hole. I'll get some 18 since it will be slightly easier to weld than the 20.

I've been doing all my floors, patches etc for my boat sides with 16 g. It's doesn't form too bad, is easier to weld than thinner stuff. Most rolling forms I can do with a hammer, for sharp lines I just cut a few slits with a cut off wheel then welded them back when I bent it. I've had some pretty ridiculous corners and what not I've had to make too