I didn't have the same style of blowgun as the source object so I designed my own parametric version. I found that the 30 degree version works better with a longer nozzle (the needle style nozzle in the photos) and the 45 degree version works better with a shorter nozzle (the brass nozzle in the photos).

The positioning of the blowgun and markers/paint pens are a bit tricky to get perfect but all the Sharpies (fine point and chisel point) and paint pens I tried worked once you got things lined up.

Example object painted with this device: https://www.thingiverse.com/thing:3387458