There are two parts to this, a plate to mount the Gen6 board on the Prusa top bars, and a fan mount that allows you to mount the fan above that. The fan mount can be used separately.
For the fan the mounting holes are fixed, but the fan aperture hole, thickness and pad height are parameterised so could be adjusted for a different fan size.
There is a third file to print the board to mount and mount to fan spacers. These are optional if you have an alternative. Again these are parameterised to alter height, hole sizes etc.
In the gen6 mount scad file there is an optional line that you can uncomment. This will add a block with a hole though it that can be used as a filament guide.