Drill guides

Two-post drill guides

• "Frankly, a lot of time I just use a piece of hardwood with sandpaper on the bottom and a hole drilled at the drill press to act as a guide."

More eclectic

• Bullseye Bore [amazon]
  • "BullseyeBore Core is compatible with most commercial electric drills with a flat metal chuck face, standard keyed/keyless or ¼" hex shank chucks, a bit hole ≤ 0.56" (14.2mm), and max RPM of 2500 or less. Incompatible with rotary or non-metal chucks."

Bubble level — 3D printed

• https://www.thingiverse.com/thing:5171048
• https://www.thingiverse.com/thing:3008076

Bubble level — Other

• https://zusellmk.click/product_details/29674947.html

Bubble level — By hand

• https://www.reddit.com/r/Dewalt/comments/13jbebz/drill_level_attachment/
• https://www.ebay.co.uk/itm/374825134059