tailgate handle, hole repair

hey guys, i need a lil talgate help. somethin has come loose in my 78's tailgate. i can wiggle the handle around and get it to work, but i wanna fix it right. i see the three bolts that hold it in place, but do i need to take the tailgate apart? also, i wanna relocate one of my toggle switches that i have mounted under my steering wheel, but what can i do abt the hole that will be left? i cant weld it up, so what do i do? thanks yall.

I think they make a plastic putty that you could put in the hole and smooth over...

Walmart sells some fiberglass patch material. I'd get some of that, and patch the hole. Sand it down and paint it.