I used a 99 5.2 with a 95 harness. I had to swap over the throttle body sensors from the 95 as the connectors had changed by 99. Also had to drill and tap a hole in the intake manifold for the coolant temp sensor that the 99's don't have. I also changed the speed sensor connector to match the one that fit my conversion. Without the speed sensor hooked up it wants to stall on decel when coming down to an idle, even with the clutch pushed in. Also the 95 computer is calibrated expecting 40 psi where the 99 is 50psi. I'm running a GM LS1 58 psi filter/regulator so I swapped to smaller injectors to make back the difference in fuel flow. It ran with the stock injectors, but too rich.