I suspect the wire rope is a safety cable to keep the TV from becoming airborne in a crash. (Either that, or it connects to a bell somewhere that rings if you pull it, alerting the driver to let you off at the next stop!)
It looks to me like the cabinetry was at least partly put in place after the television was mounted. I'd hunt around for ways to remove it. The cabinet framework appears to be assembled with pocket screws, which should be easy enough to disassemble if nothing else presents itself.
I also suspect a relatively thin open-end wrench (not an adjustable one) would be able to loosen the nuts on the four bolts, at least until the other end of the bolts got loose enough to start spinning with the nut. Maybe a person with pointy enough fingers could hold the two closest to the windshield still by reaching over the back (front?) of the shelf, but the other two look more doubtful. It would be a miserable job to remove things that way, at any rate.