Since this will be the only source of this process on the Internet1, I figured I'd document a quick fan swap I did on a piece of test/reference equipment I'm running in my Atomic Clock Tower. I took my Torx T10 screwdriver and popped off the top cover. The screws required some force to loosen, as they were all secured with Loctite. The inside is simple and serviceable. There's a SpectraTime GRClok-1500, with an integrated timing-grade GPS module, and a stabilized 10 MHz output2.