Thanks for the input guys!I am going to spray the inside of the frame with self etching primer ,and "lightly" spray the outside.The main reason I wanted to sandblast the frame so soon is to have a clean base for welding.I am sure once I have welded the new boxing plates and crossmembers in I will have to take it back and lightly hit it again with the sandblast,then straight to the painter,or powder coater.I kind of got the buggy in front of the horse on this one ,but nothing major.