2G Steering wheel spline dimensions.

[ileagleracing]

Does anyone know the spec's/dimensions of the steering wheel spline?
I'm allowed to change steering wheels in the class one of my cars is in, but the wheel can't weigh less than stock, so I wanted to design a weighted steel adapter to make the swap legal.
Looks to be around 15mm, but not sure how many teeth and the actual teeth size.

 

[EVLGSX]

Cut the splined hub off a junk 1g wheel and weld it to whatever you like. Easiest way to put whatever wheel you want in a 2g DSM. Theres info on this pertaining to installing an evo8/9 wheel around here somewhere