Probably depends where they dump. If its under the driver, no. If its under the back bumpers like the fox body GT's, yes. I know the law states that the exhaust needs to exit behind the cabin of the vehicle, like side pipes, etc.
He is correct. Exhaust must exit from behind the passenger compartment. This means you can do side exhaust or regular rear exiting exhaust. Other wise it it illegal.
Hmmm, i was never told that. On my 5.0 i originally had headers, catted x pipe, flowmasters that dumped. An exhaust shop even installed all of it. I took it for emmission testing and the guy said he couldn't test it because it was to close to the axle and his tube would catch on something...although now i look back on it i don't know what it would have caught?