[Dominik]

good morning,

I am not sure if it helps the issue, but in the early 90s I ordered two sets of six-pin knock offs from Contemporary or Cobra Restorers (not at the same time, but closely together).

for the second set I got wing nuts which sit too deep in the taper of the wheel, so that the rims were actully held by the "wings" causing them to show a lot of "runout" or wobble.
and not by the taper.

both sets of wing nuts were aluminium with embossed HALIBRAND logo.

thread was the same, but I admit, I never checked the taper.

dominik