It may work fine.......and that may be the way many people have done it since the beginning of time.........but it also doesn't mean there isn't a better way. The chassis itself is a POOR conductor of electricity
Depends on the chassis. A unibody might be a poor conductor but anything with a cage in it should be just fine. Even a set of frame connectors will tie the rear subframe to the front subframe and give the battery a low resistance ground path to the front of the car. Easy enough to check with an ohm meter.
