OK so it is prep time. No need to go into crazy detail. I use 320 alu oxide (because it holds onto the paper well and doesn't turn into slurry) and I sand wet. Always. Few reasons. I use a cleaning liquid. This makes it smell nice, has detergent which lubricates it, and keeps the mess down. Problem with dry sanding is you need to wet it at some point any way to see how it is. And to clean it down.
Panels were removed.
And then sanded well. The original finish was like a satin, but had a texture. I wanted that gone. Just remember, you don't need to go ham here. You are just wasting your time. Get it smooth, get it keyed. You don't need to sand down to metal unless you have damage or rust, and in this case there are none of either.
The evidence is on the board. You can see what I am using there. It's skin friendly, so the nice part is you can not only wipe the panels down with it to transport them, but you can also use it to clean the slurry from your hands. You are aiming for a nice flat finish.
Parts are still wet. I just know it's right, as I do it by touch.
Just remember, sometimes logos are quite deep. Like, almost etched. You want to keep going until you can't see any of it any more. Not paint, anodising and so on. If you leave it? you will see it through every layer of paint you put down. Thankfully this seemed to be a thin screen printing of paint, so came off very quickly without me having to keep going down.