How to make a car look burnt out for Post-apoc?

[SBRPearce]

Looking at photos of burnt-out cars, I'd try the following steps:

• Lose the tires - they melt
• Windows, obviously, go the same way
• The interior is usually reduced to char and rubble. (Interestingly, the internal structure of the seats has a fair amount of metal which may be modeled using fine wire)
• Modern cars have plastic body panels that succumb quickly to heat - even a car parked near a fire can end up puddled just from the radiant heat. IN this case, the steel chassis is exposed
• The paint burns/flakes off from the top down and the center of ignition outward
• Your primary color overall is, initially, flat black from soot and almost instantly goes to "50 Shades of Rust" as the steel now lacks any protection

Have fun with the weathering.