I just got my new Impact Wrench, the Ingersoll Rand 2132G 1/2-Inch Edge Series. It’s amazingly quiet, and has plenty of torque. If you still have a cheap-o impact I highly recommend getting a decent one, there is not substitute.
Ingersoll Rand 2132G 1/2-Inch Edge Series Impact Gun Wrench
The info on the impact gun is great but the camera is getting me seasick. After you explained the gun, you are wandering around the garage and the camera is moving too much.