I don't know that I would call it completely flat in sheen.

I've done a few, in different colors and they all have a VERY small amout on sheen to them. not enough I would call them satin or gloss by any means though.

I'll see if I can find a picture of one I did recently

edit,
no pics on this PC,
I have a 1970 B-body column on the bench now in baltic blue. I'll snap a picture later today to show it.