KH disks to 5x4.5

Hey guys.
I am thinking of changing the size of my bolt pattern to the newer 4.5 size. It currently has the 5x4 KH disks up front and not sure on the rear as I havent had them off yet. Is there an easy upgrade hub for this and keep my KH discs as they look to be a fairly good size for the car once I rebuild the calipers.