Can front disc brake swap work with OEM wheels?

The 73-76 factory brakes are sweet. Bolt right on with upper arm swap also. Buy parts at the auto parts store. And a stock 14" wheel fits over them.

What's not to like?

Aftermarket 14x6" SBP rally wheels don't fit over stock Kelsey Hayes SBP factory disc brakes. Why would they do that?
Sorry, I'm a bit confused there. You referenced "Aftermarket rally wheels." Are these aftermarket then (14 x 5 1/2)? And would places like Summit, RockAuto, O'Reilly's carry everything I would need for the '73-76 swap? Reckoning they'd be individually bought, not as a kit. Thanks again for enlightening me! BTW, this isn't my car, but I may buy it...

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