Thanks for the tip....but I'll be welding it in. I have gained a lot of respect for the guys that do this everyday. I have had the skin on and off a half a dozen times...I will win but this takes a lot of finessing.
I agree it's a a little daunting at first Alex, but if I did both of mine with a flux core HF welder, I am so certain yours will come out great.
Never convince yourself to run a weld longer than 3/4" or so. Just stop and move over to a spot on the opposite side of the panel. Move around on the panel. I cooled mine down with a wet towel as I went.