I am building a ported enclosure and am wondering how everyone paint their ports all the way to the back. I have thought about painting the port before i put the box together but i just wanted to make sure there wasn't a better way to do it. My port is pretty small, 2.5" to be exact, so I cannot reach my spray gun inside it.

carefully

Round port or slot?

Round port there isn't much option but to paint it first.

Slot port you can do the same way. Be sure you tape up the edges that will be glued or it wont bond correctly. An alternate method is a small trim roller with an extension. Much easier to paint before you put it together though.

it's a slot port. im just going to pre paint the port then. thanks

I pre paint mine first.

kinda like so.