i found a jet performance module for my truck (92 f150 300 6) that will work with automatic, i also found a shift kit that plugs into the computer that is from jet performance. I just wanted to hear some thoughts about jet performance and wondered which i should get, or both if they can both be used at the same time. So which should i get? and can they both be used at once or is one or the other? and are they worth it has anyone had them?