i've done a search but haven't found anything definitive. What I would like to do is spray my brackets from a gun, not a spray can. I've concluded that 30 percent is the right gloss. I would like to know what paint I should use that I can buy in Ca. that I can flatten to the desired results and have durability.
The Eastwood Underhood Black says 10-20 percent and is acrylic lacquer. I'm told it chips easily but I see Eastwood claims to have changed it's formula to combat this. Has anyone used this with good results. What did you use? thanks

My observation is that chipping usually comes from the paint being too thick.

I would buy a can of ppg delstar and some flattening agent and play with it. If you want to spend a little more money buy some DCC urethane.

Powdercoating is the most durable solution, but you can't control the gloss factor with it like you can with paint.

I would not go 30% flat! Just use Eastwood underhood black. It's easy, sprays nicely and looks great. I have my pulleys, fan and brackets powder coated semi gloss. It looks fine if it's a little glossy but not too good if it's too flat. You don't want your radiator too flat either. I would stay away from trying to do a certain percent flattener. It's tricky and there are plenty of good paints out there of varying glosses.