Decals

[Okiespaniels]

I think a showboard, some painted and/or dark anodized engine details, and a smattering of other interior details will go a long way.
Maybe some ghost flames a shade off the original color would work. What ever you paint should not hide the finish.

Again, the unique color of your truck is its greatest asset. Conversley...it's a dark and foreboding shade...any theme in the truck should reflect that. That doesn't mean you need to make it into a gothic beast. But its never gonna be a bright and happy truck and I don't thnk you can turn it into one.