I have a 1991 Ford Mustang LX 5.0 with a manual transmission. Is it possible to start the car by towing it with the rear wheels on the ground, in first gear and with the key in the run position?

I agree, don't use first gear. Make double sure it is not in reverse, use second gear.

When you pop your clutch, be prepared to push it back down and keep the gas going. Towing to start is a little dangerous as when it starts and you give it gas to keep the engine going you have a tendency to run into the tow vehicle!

Thanks for your replies. I asked this question, as this car was being towed with the rear wheels on the ground, in first gear and the car in the run position, After doing so the tow truck driver pulled over to the side of the road and there was white smoke billowing from the tailpipe and fluids leaking from the back of the motor. The car was then towed to a repair facility and they determined that the engine had seized. The owner of the tow truck now claims that it's impossible to start the motor under the conditions mentioned above.