I bought a set of Mato Panzer III but it was not indicated it would fit HL shaft... They look identical to the ones you used on your Hummel but there's no pics of the back showing the diameter hole. I've just sent a message to Toucan to see if he can give me the answer...
I'm using a HL panzer IV gearbox, I believe they are the ones with the long shaft (I'm still new to HL stuff
) and the gearbox are almost touching the side of the hull so I can barely move them if they're too short... If they are too long I'll cut them on the lathe. Thanks for the reply!