2001-2007 Interface Module Tachometer Digital To Analog Duramax 6.6L (112030000)Description We doubt you have had to equip your Duramax with an old dash, but many of you are equipping an old classic truck, 60's era muscle car or even a ski boat, with a Duramax engine. In either case, you have probably discovered that you now need to make your new Duramax electronics package compatible with the wiring of an old school analog tachometer. PPE has solved the problem for you. We spliced the wires and put the whole step into the PPE