have my "Hungary holiday" used; go to my Red-Lady from the bottom of the rust.
I have the underbody, the rear axle, the tank, the wheel wells, the shocks, all lines on the lower floor (steering, brake, fuel), the propeller shaft, the rear differential, let sandblasting.
Then had my car 5 small rust holes ("underbody right-front", "underfloor left-behind", "wheel-right-back," "floor plate-trunk", "tail plate-trunk").
Then my friend (coachbuilder) removed the rust and welded in new plates. All seam seals renewed, all bare attachment parts with "flat-black-paint" finish.
All cavities (sill frame) treated with wax.
The subfloor with "rubber Stoneguard" treated, and then the subfloor with "bitumen underseal" painted.
I think this will keep the next few years before new rust comes.
Greetings from Germany