12.9s would be fine if you're giving them a beating. From memory, they're standard (coarse) pitch. Kays will have some.
I once tow started a loaded Transit diesel pickup belonging to some nice Irish gentlemen, using a rope looped onto the towbar attached to mine. The bumper plus towbar has stopped a couple of low speed impacts with nothing more than the stock two 8.8 grade bolts each side. Outbreaked a Vauxhall Corsa from 55 downto to 0... they hit us when we were almost stationary.
Hello everyone, looking at the old VW picture parts catalogue at page 056-00 part #31 it is 4 times a M10X22 (VW part# N 010 253 7) - that could be found at images with 8.8 The latest Westfalia hitch 321 125 (8.1976-7.1979) for up to 1800kg uses 6 times M10x25 and 2 times (left and right at the sides to the front) shorter M10x22 but all with 10.9. regards,
