Shot the bus with Krylon clear gloss to install the decals and do a wash for the scribbed lines. I then gave it a clear matt coat (Krylon again) 24 hours later. This was not done without some amount of stress. Last time I used Krylon clear was on a Tamiya Porsche 911 GT2 full of decals and the entire thing went orange peel on me! This time I used the "craft" Krylon clear rattle cans and besides being worried after the last matt clear coat looked kinda white, it all dried up real nice. As you can see in the last image of the hub caps, I use artist oils to do my wash. They have the finest pigments and it really brings up the details.
After applying the matt clear coat.
Hub cap on the far right is without the wash detailing