I've got a Mac Pro 3,1 that I'm going to use as a Plex server. It came with 16Gb of RAM, pulled from an HP server, with slim, non-Apple heatsinks on the 667MHz RAM. It works fine and has had no issue. Everything I've read has lead me to believe that I need the bigger heatsinks to avoid heat issues later on. I bought 64Gb of 667MHz RAM for £38 on eBay. It came with the same slim, non-Apple heatsinks. I also bought cheap Apple RAM with the giant heatsinks on it with the intention of pulling the heatsinks to install on the 64GB of RAM. I've googled it, but have no idea how to do this. How complicated is it? What tools and supplies do I need?