On my race car I used Aluminum tape to close gaps. It's got a peel and stick backing, it's about as thick as duck tape, forms like aluminum foil but takes a bit to knock a hole in it. Heating and air supply houses sell it. Not sure you'll find it at places like Lowes.
Wanting a Custom fit in an off the rack world.
I don't have time for a job, I just need the money.
