You should give Jeff a call. They will be more than happy to answer all your questions.
The body thickness is about 3/16th if I had to guess. I keep mine in an uncovered patio but I have a cover for the grill. There are some rust spots on the top of the grill that appear from time to time but they usually just wipe or sand off and I just spray with high temperature stove paint. There are probably better solutions to this but I haven’t been worried about it enough to really think about one.