SSR wheel bolt size

So i just bought vienna dish's used and i need the right 12pt or triple square bit because i am taking them apart to refinish them.  I bought a 8mm cause thats all the local auto store had.. it just barely doesnt fit.  I would think its a 7mm but cant find a 7mm online.  So is it a 6mm triple square?
Any help would be greatly appreciated :pat:

[IMG]http://i981.photobucket.com/albums/ae295/selah777/ssrwheel.jpg[/IMG]

You loosen the back nut not the front one.

Well i know that.. But dont i need to hold the front in place with the appropriate bit?

Well i just used a torx bit. Its enough to hold it thats what i use on mine

i was just afraid of stripping it out.  Thanks for the help man ill see if it works