Hi Gene,
No, he didn’t say, but, I’ll ASSUME it’s best to clad BACK to the F-body transmission crossmember and weld frame connectors in at that point to tie everything together. I’ll also ASSUME it’s best to go as far forward as possible (at least to where the bumper bolts to the chassis. That’s the plan… Also, looking closely at the F-body rails, it looks like the sheet metal is lipped together and spot welded (is this clear?). I suspect I’ll have to cut off the protruding lip portion and seam weld it together. That will make it smoother for cladding.

Greg