So this is what I was starting with. You can see here I've already masked off the underside. There is a heat shield on the underside and I didn't want it to get covered in paint:

The paint finish is a wrinkle finish but I don't know whose paint it is. The main objective here was to make it look good rather than make it look exactly as it did from the factory. I wanted to get everything as OEM looking as possible but needed to draw the line somewhere. So in this case I selected a VHT wrinkle finish and after a quick clean and dry I painted over the existing finish. With wrinkle paint you deliberately let it go off a little bit and then spray another coat over it. You do this several times then leave it and it goes from being smooth to all wrinkled over a period of several hours. It takes days before it goes off properly and it stinks in the meantime!

Wet finish applied;

Here it is after the paint had wrinkled (several hours later):

The camera flash makes the wrinkle finish look a bit odd, but it's a pretty nice finish and close enough to the original for me.