I think I didn' state the texture suggestion correctly, I'll try to rephrase with an example.

I should maybe say there are not enough material zones : for instance the material "glass" covers all the windows, it would be easier if there were separate zones for the windshield, the front doors, the side doors and the back doors. The "hull" material covers body, hood and doors : again separate zones would be better. Same for "metal" and even "chrome".
It doesn't matter if you only provide 1 texture, as long as we are able to assign a separate texture/ material for (about) every part of the van ourselves.

The Ford GT and the AC Cobra found at Posetteforever are good examples.

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