Modified X-mount for more screw clearance

I paired with this fan shroud I remixed:

https://www.printables.com/model/862583-ender-6-magnetic-fan-shroud-spider-v3-noctua-4020

-increased the clearance around the two v-wheel screws b/c my linear rail mount made the screws interfere

-also added some alignment tabs to make the help keep the shround from being able to shift. 

-also added 3-mm more thickness to shift the shroud 3 mm forward b/c my modified shroud interfered with the X end-stop.