What are the latest suggestions to protect inside sub structures from future corrosion? Just had all rust cut out and new sub structures replaced - rocker panels, rear A-arm supports, rear door opening pillars, etc.
Have read a number of posts suggesting the drilling of additional drain holes, wand spray undercoating inside the structures, and the pros & cons of spraying foam in the inner channels.
What seems to be the latest technique(s) to work?
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