You are going to need a new Ring & Pinon set. You need to be within 1% difference from front to rear on the R&P. 4.90 & 4.56 you are at a 7% difference. So basically the front and rear driveshafts would be spinning at a slightly different speed eventually (sooner) there will be a failure in the drivetrain, Ujoints, Driveshaft, Tcase somewhere something WILL snap.

You need to get a set of 4.88 R&P to run with your rear axle. That is only a 0.41% difference.