Major Rob

I use Model Master gun metal or dark sea blue and use a dab of Future or any other type of clear coat to give it a slight shine. Dry brush the upper portion to make it a little lighter. Heavily dust it or muddy it up if you don't want to bother.

Thanks Major. I'll give that a try.

Holy cow, I didn't even know they had clear and half oil-filled road wheels. What's the function of that?

The oil is to keep the bearings lubed. The cover is clear so that you can quickly see the level of oil in the resevour and make sure there is enough present for proper lubrication.