The 10 71/48-inch rotors on your car can be swapped for the nearly 12-inch units used on late-'70s R-body models, which include the Dodge St. Regis and the Chrysler Newport and Plymouth Gran Fury that share the same body style. You can also find these brakes on some late ('70s) B-body models, like the Chrysler Cordoba. The bigger rotors, which can also be purchased new from any auto parts retailer, will mount on your existing spindles. The key to the swap is the caliper brackets that accompany the 12-inch brakes. By swapping your stock caliper brackets for the R-body pieces (a direct bolt-on), the calipers will be repositioned appropriately. You can even retain your original calipers. Since the calipers don't change, there's no need to make any changes to the hydraulic side of the brake system, like the master cylinder. Making this brake swap will require you to use at least 15-inch wheels on the front of your car, though since your cop car came with 15x7-inch steel wheels, this shouldn't be much of an inconvenience. This brake swap works on F-body Mopars as well (Aspen/Volare), because the chassis is virtually the same as the M-body cars like yours.