I have cleared the cache multiple times since these issues began and prior to making this thread, so DON'T waste my time suggesting it. I'll get straight to the point, I could use a hand identifying any mods that add any parts/configs to the Ibishu Miramar prior to 0.36 that don't explicitly have either "Miramar" or "Ibishu" in the name. As for the problem itself, it's simple: there's some conflict with the coupe body that's causing a duplicate of sorts. The result is that the glass on the couple body is completely mismatched, as pictured here. I've disabled every Miramar-related mod I could find that hasn't been updated since 0.36, yet the issue persists. If anyone knows if there's any pack-type mod that adds a body-type or whatever to the Miramar, let me know so I can disable it and see if it makes a difference. While not as much of a priority, some help with a smaller problem I've been having with the D-Series would also be appreciated. In that instance, for whatever reason, the roof will have a dent in it the moment it spawns, as pictured here.
The mods causing that roofline is very likely either this: https://www.beamng.com/resources/miramar-coupe-body.14698/ and/or https://www.beamng.com/resources/ibishu-miramar-690-710-coupe-and-convertible.15441/ since both have a coupe bodystyle, and that's overriding the vanilla body. The D-Series I'd wager the same thing, but honestly don't have much of a clue since I haven't really used the vanilla version of the pickup for a long while.
Wasn't subbed to the coupe body mod, but I was subbed to its newer version as part of the "Stuff Pack". Disabled it and that fixed the problem. Thanks.