[Marwil]

I think the last time these type of things were available they were 14 or 15 gauge (about 0.070") - this is apparently the thickness that the factory used for the early Carrera race or rally cars. Lots of people here who are way more knowledgeable than me on the details. If correctly preformed I think 13 or 14 are doable and would really strengthen the chassis - 18 or 16 gauge might be too thin and the potential gain might not merit the effort required to prep and weld them into place.

Mark