I never bothered to check how much the holes need to be opened but if its as small as 1968... says, "flipping" is a good option also. Either way, "flipping" or adjsutable hangers seems to be the best way to go. Its very easy to do, you will have good spring, adjustability and it will cost less. Just be sure when you are done to check the pinion angle and make sure it's good or else you will get vibration and risk u-joint failure.