Spent the day finishing up tasks. I touched up the paint on the inside of the upper cowling. I replaced the original hinge on the oil service door (.0880 diameter) with one that had a longer bend so it could be safety wired. It was then safety wired. I finished installing the foil heat shield in the lower cowling. I called B and C and talked with their OVM-14 tech "Greg". I asked if testing the Over Voltage Module with 24v would hurt it. He said no, and that the OVM will trip at 15v. I put two 12v batteries in series (24v) and applied it to the unit and it did trip the breaker as designed. With the unit fully tested, I installed the Ground Power Unit and wired it completely except the final connection to the Battery.