Hi
I had 944 backing plates narrowed on my old 1302, it ended up with the wheel bolt being only being a few mm further out over stock.
An easier solution would have been to use a Type 3 centre section, mount the 944 rotor on that then make an adapter for the stock calliper, you would still get a track increase, the thickness of the 944 rotor centre over the Type 3 drum centte thickness. Only problem then is the E bake. A Willwood Ebrake calliper could be used. Our local authority engineers would not allow me to use a non OEM ebrake calliper, that why I went the narrowed 944 backing plate route.
Steve
My billet hub
My narrowed backing plate
