So, I don't weld and I'd be worried anyway to weld with the gas tank being right there.
Side.... My grandfather died in a self-inflicted explosion cutting up cars for the local salvage yard way back in the day - got to close to fuel tank with the cutting torch - boom. BTW his nickname was Smokey because he always smoked a pipe.
Anyway back to the holes left from the A/C delete... short of welding how else can those cavities be dealt with?
BTW the evaporator coil unit that came out of that opening is available if anyone is interested.
I've never used fiber glass, but I'm not sure it would hold up.
Holes are too big for JB Weld
Thanks,
Len