There is probably a thread on this already but I can't find one. Looking at 20 inch deep dish wheels that clear the brakes. With the tire I want to use, total diameter will increase by 1.5 inches over the stock combo. Is there any difficulty to reprograming the computer to keep the speedo accurate and not screw up any other settings? Can the local Ford dealer do this? I could go with a combo that would keep the diameter the same, but I am an old geezer and the current super low profile tires just don't do anything for me. Thanks in advance for replies.