And the beginning of this is a duplicate Ultra Magnus cab, being repainted into Powered Convoy colors:

The blue paint I used might be closer to the blue of the Diaclone-homage reissue's cab than to an official Powered Convoy but it's good enough for my purposes. Now, in addition to the color changes I'm also painting the molded detail - things like the cab upholstery, the handrails, the horns and lights on top of the cab...
Now, this photo is a bit behind my actual progress. By now I've actually finished the painting work and have been clear-coating the parts to protect the paint. Also clear-coating the chrome parts to protect them from further wear.
Don't have a trailer yet, but I will be getting one at some point and painting that too.