I am lookiing for an owners manual for an "Airco Heliwelder IV- 300 amp, Model #13410176". I've tried an online search to no avail and was wondering if anyone has one or can tell me where I could find one? I am looking for this for my old welding instructor that taught at the community college I now teach at. He's been a big influence in my career for the last 20 years and I would like to find this manual out of respect and admiration for the man.