I vote world cab on the blue one, but I'm a little biased. That would require re skinning the jump seats (unless you dont plan to use them and want to sell em).
If you put the world cab on the red one it would need to be sprayed with a liner to match (I personally do t like that, but that is just my opinion). The jump seats would still need to be re skinned, unless you reskin the driver and passenger seats to tan.
The red one looks ready to roll around the island, so I'd just use the heck out of it as is.