that's an interesting idea... although how do you explain retro Al having an alloy boot floor (that's removeable and leaves a massive hole) or that my turrets are chopped into the chassis rails? or that the rails on both our cars and the one above have been notched to allow an extra inch or two of suspension travel when running at really low ride heights?

i think it's just if it's corrosion that that rule comes in to play, not if it's a deliberate modification and safely/properly done...