If its to be a factory stock deal, don't drill extra holes less your planning to weld them up after wards. Eastwood has a spray deal that has flex wands for the tip, I was thinking about using it to apply epoxy in the hard to get to panels. Also was thinking about doing the phosphoric thing before the epoxy too.
The place that does the job should know how to make sure theres no chem left in the pinchwelds etc. I think heating those areas would help.
