all vanagon seam rust comes from BEHIND.    you can spend  hours and days
treating and sealing the area from outside but it will ALAWAYS  come back if
you dont treat it from the INSIDE or the back of the panel.

ALL drivers side westy rocker seam rust comes from BEHIND....

i say this time and time again, and nobody seems to care.

when the Westfalias arrived at Weidenbuck germany for conversion by
westfalia-werke into campers, they came from Hannover as a pre-painted painted,
running, driving shell with no poptop or camper interior.

westfalia-werke then cuts the 3 square fill ports in the side of the  van.

they simply apply a self sticking pre-cut gasket around the fill ports and
bolt the fill ports in.

25 plus years later, these foam gaskets have long since disentigrated due
to mother nature.

water leaks in the fill ports perimeter every time it rains, or you wash
your van.

it runs down inside the drivers side wall, soaks the insulation behind the
kitchen galley, and never really dries out..

the holizontal body beam under the fill ports starts to rot out, and the
floor/rocker starts to rot out.

water then seeps thru the seam and starts bubbling out the drivers side
rocker seam from behind.

drivers side westy seam rust has nothing to do with road  salt.
if you have a westy with leaky fill ports in Arizona and you wash it every
day it will have drivers seam rust too.

the moral of the story -
got drivers side westy rocker rust?

must pull kitchen galley and treat from behind and re-seal fill  ports.

no other way of getting around it.