Slowly working on my own UDS build...
Can you buy the expanded metal at the HD website and have it shipped to store? For the prices you're talking, it might be worth your time to consider the Big Poppa Smokers drum kit that comes with a pre-fab charcoal basket and step drill bit to boot, plus all vents and hardware for $130. Big P says they'll be restocked after Xmas rush sometime mid January.
For about $5 you can get a titanium-tipped drill bit that might pilot out some holes so a less expensive step bit would probably do the trick.
Wished you lived closer to CA or I'd offer to trade drum lids with you... mine has bungs but I'd prefer a flat one!
I plan to have the lower bolts in place so they're there if and when I want to use a deflector or pan. Rather do it now and not use them than decide later I want them and have to go back to fabrication.