Another update. Turns out my vinyl won't be arriving until Monday or Tuesday, so still only one door is wrapped. But, got to make the grills today, and that was a fun process.
Started with 14 1/2" MDF rings (8 for the 6's, 4 for the 10's, and 2 for the tweeters). Used my amazing toolmaker machined router jig:
Then, hit em with a roundover bit:
Next came some primer (note: LOTS of primer was used for the grills thanks to MDF being so porous and soaking in paint like crazy:
Let them all dry, then filled in any holes. I brad-nailed the rings in the above steps so I could safely router them without and funky/sketchy hand action. I also hand sanded the rounded edge to a smoother finish, as well:
Tough to see in this pic, but I routered some holes into the back sides of the grill rings for the grill bars then followed up with some fill primer: