I was growing crazy trying to get the lower V-wheels attached and discovered one of offset nuts has no threads. Its drilled large enough that the bolt spins freely. Then looking around the parts I see two other offset nuts that look different and they both have proper threads but they are a really tight fit in the install hole. So what I have is:
2 x Chrome offset nuts with a v in one of the flats. One has threads, the other doesn’t. These nuts fit very loosely and even fall out of the hole while installing.
2 x Stainless offset nuts with threads and a little shoulder (like an attached flat washer), both have a small round dimple in one flat and they fit very tightly in the mounting hole
The other 2 should both be un-threaded and are used on the EZtram plate (if being used) It sounds like you have got a mixed bag there, if you email into support we can ship our the replacement eccentric spacers.
Actually I was in error. Neither of the chrome nuts had threads but one of them tricked me. Proper nuts are now installed. Unfortunately missing a M5 x 10mm. Going to recheck inventory before proceeding.