Mike, sorry to disagree, but the hubs are not the same. Yes it's true the discs are thicker but to compensate for that Porsche made the Turbo's hubs thinner than the N/A.

In short...

thick hub/thin disc = N/A
thick disc/thin hub = Turbo

Reading many experiences (on a 944/951 forum) from Porsche owners I've learned this type of mixture of the Turbo and N/A parts is next to impossible to make work correct. Some that have gotten the calipers mounted with custom brackets reported problems that the Turbo calipers would crack the thin N/A discs. In the end the conclusion and what ended up working for a few were Boxster monobloc calipers on N/A brakes. The Boxster discs are more the size of the N/A for better fitment.