I just had David, at ETDRAG.com, install a Mag-Hytec differential cover and a full set of gauges (boost, EGT, transmission temp. and differential temp.) on my truck, using a quad pillar mount. He filled the diff with Royal Purple lube. I am very happy with the work he did for me. The price was reasonable and the work was excellent! I'll be more than happy to go back to his shop (ET Motor Sports, in Pasadena, TX) for any other work I need done.