That heatsink has two options for installation. One option is lower profile using only some of the parts that come with the heatsink and SHOULD fit fine under your graphics card. The other option using all of the parts that come with the heatsink probably will not work with a gaming card installed.
Truthfully, the use of a heatsink is not a requirement especially since that M.2 drive is fairly efficient and in fact during the TH review they tried but could not get it to throttle so temps are probably not going to be a problem with this drive since it's DRAMless anyhow and with workloads big enough to potentially cause throttling in the first place, it is probably going to bottleneck itself into fairly slow speeds until the pseudo cache clears anyhow. I'd probably not waste the money on a heatsink for this particular drive, if you go with this particular drive.