they are in pretty good shape dont think they need any welding, will have a look when home for the instllation hardware, still have the hoses on the car, not sure about the pump will have to confirm on that
Woick in Germany used to sell them, 60 l each side. Filling in the rear wheel arches in front of back wheels.
If you have a body lift of 40 mm, you can increase the height. On my 290 I did the effort to make new tanks with the same bottom line, 40 mm taller, 75 l per side.
I have the Woicke ones Rolf. They’re nice but so stick out a bit under the standard body lift so mine are out for some cosmetic dent removal total fuel increase is 120l ah I will get you far, even in sand.