I ran into heat creep issues while using the heavy duty e3d v6 mount (https://www.thingiverse.com/thing:2494642) when running at high temperatures for several hours. The reason was that the air that is supposed to cool the heatsink gets trapped between the x-carriage and the heatsink mount.
In order to resolve this, I remixed the mount with the heatsink fan on the side. Consequently the part cooling fan now has to be mounted at the front, in order to not block the air again. For that purpose the new mount has three mounting lines, that are compatible with the original model. Using this thing (https://www.thingiverse.com/thing:2775921), one can use the stock part cooler.
E3D SpoolWorksPro Petg
Print the heatsink mount face down, while the carrier mount should be printed upright, it has custom supports to speed up the printing process and cut down on material cost.