I'm doing a cummins swap in a 2007 GMC T7500 with the 7.8L Isusu/Duramax L6. I'm not getting a tach reading on the dash and was hoping to be able to connect to the ECM with efi to diagnose. Is there any chance of this? Here's a photo of the ECM, matbe there's a comapatible one in the list or a trick or two to make it work!