Taking apart a pair of wiper arms and noticed for first time they are different overall lengths and different lengths between bends. 28 years of vanagon ownership and only now saw this, ha!
Close up of part numbers on arms. 251955409
Compare to the rear wiper, mirror image, not swappable.
Photo of South African T3, Same rear wiper orientation as left hand drive. Photo taken from the Samba. Oh btw, my rear wiper part number is 251955707.
Update February 13, 2020. Got the arms back from powdercoat. I had them blasted and painted with slight texture finish satin black. They look really good, pic doesn’t fully convey the nice finish.