I'm very interested in this thread/topic. For years, I always did this;

- 1) mechanically removed rust; wire brush/wire wheel/sandpaper or sandblasting (if feasible)

- 2) etch/convert the surface with acid or one of the "phosphate" type converters.

- 3) cover with primer/paint to prevent moisture and oxygen from reaching the metal.

....BUT, it seems with all the products and all the hype/claims, it is VERY hard to determine what is the best product(s) to use. Like many people, I don't really care what it costs; whatever the cost, it's cheap compared to cutting, welding and rust repair.

Here's some links I found;

http://www.drjing.com/Mini/BLOG/SideBySide.htm

http://www.thesamba.com/vw/forum/viewtop...sc&start=40

Dave