Does anyone know about sacrificial anodes use for cars? Or the electrical protection systems they sell? How effective are they if at all. On cars.

I am not computer literate enough to post pictures. Yet pictures of actual rust do help. Geographical location determines to what extent rust develops.

In the salt belt where we live we actually look at it as having three stages. Although it is just the same oxidation of metal attempting to return it to its natural state again. Most miracle paint type products are moisture cured urethanes.

Sounds like superficial surface rust in your case. Probe with a screwdriver or awl if uncertain. In the 1960s and 1970s Mercedes had horrific corrosion issues. In some regions of north America. Mercedes knew it and still persisted with the same methology on their unibodies. Worse than no protection of their metal at all in our region.

Theoretically the better bond the urathanes or epoxies have the less chance of oxygen getting in and also perhaps less space for condensation. Dealing with rust on these cars is harder than most I tend to believe on average.

Oddly enough although I have not tried it. I have several electric paint removers that may heat that sound dampening material enough to soften it to remove. Not heat guns. You do not want to make a mess of the interior when getting prepped for whatever you decide to do.