Painting door hinges

I have my hinges apart for a pin and bushing kit from Resto Rick. It looks like he paints them after they are reassembled. This would be good for me as I still need to mock up my body to check gaps, etc. But it looks like it would be hard to get them covered in paint with all the contours.

Do you guys paint them apart or assembled?

What is the correct finish for the bolts?

Mine have some trace of body color on the cowl bolts but I can't tell on the door bolts. I would think the hinges were painted on the car at the factory but I don't recall ever seeing one where the hinges were painted to the door or pillar. Maybe they just didn't spray enough paint in that area to glue the hinges to the pillar?