Here are some "after the fact" pics of how I drilled the vents in my UDS lid. Hopefully, it will help someone else that's lazy like me.
I decided how far from the edge of the lid I wanted the holes.
Then, I cut a strip of wood to the length that would just fit inside the top of the lid at that distance from the edge.
I made two marks on the wood that centered the two holes.
Then, using the marks on the wood as a guide, I marked the location of the holes on the lid using a sharpie.
After I marked the locations I went back over them with a punch to act as a guide for the drill bit.
Using a square, I was able to move the wood at a 90 degree angle from the first marks.
I marked the second set of holes.
I repeated the process until all 4 sets of holes were marked.
Then, I drilled out the holes using a step bit.
Easy peazy and no need for an elaborate template, just a strip of wood, a tape measure, a square, and a sharpie.