OP replied to my DM, but in the interest of keeping the info from his project all in one place, here is his reply:

1. Printed on ABS
2. Haven't seen any issues with heat, I also have not removed and inspected anything since I completed this a year ago.
3. I did not trim the shroud and I absolutely regret this. It is so close but I did have clearance so I thought I was good. Nope, I completely forgot to take account for aiming and adjustment. So now I am maxed out on vertical height due to my lens hitting that shroud, it's tolerable but I would like to aim my lights just a tad higher and I can't do that at the moment. I have plans to take the lights apart again, trim and probably change projectors.