Why did my trucks catilitic converter melt off the truck?

OK you'll like this one. I'm pumping gas in my 1981 ford f250 with an inline 6 and a 4 speed. Next to me is a mustang with no badges but snorcals on the hood. I ask him if its a gt and make small talk. He admires my truck. I drive out of gas station over freeway and truck starts cutting and spuddering. It slows down from 45 to 35 to 25 quick. I drop gears to get rmps truck would run strong then have nothing then back fire then run good then back fire and so forth. I look in my mirror and see a trail of glowing orange dots spred about 6 inches apart and for about 20 or 30 feet behind the truck. I'm a mechanic and welder so I know molten metal when I see it. The first thought in my head was my Axel is melting. My axle has small crack and leaks a little but to have cadistrofic meltdown literally? I turn the truck around knowing I don't have long to get it off the road. The truck stalls as soon. As its turned around. Having had had my hazards on already I just cut my head lights to save power. I look under truck to find what was melting only to see my catilitic converter glowing bright orange and see liquid metal dripping from it. I give it a few min. To cool off. Truck starts back up runner rough. I drive truck back to my house SLOW! Just though I'd ask if this has ever Happened before.

Obviously you were running too much unburned fuel through the cat. The check engine light should have been flashing at that point. I hooked up the spark plug wires in the wrong order one time on a vehicle. The cat took about 5 seconds to start glowing. No melting though.

My I have not messed with timing I drive truck everyday. No problems. It wasn't glowing by the time I got home. Truck is as truck check engine light never came on. Thank you for a positive answer. Everybody a little help every now and then man. Truck has new fuel filter and pump. Has a new ignition system. Only 70k miles since rebuild. New brakes new clutch the interior restored and the outside prepped for paint. Yes I'm a mechanic my man iv just never heard of that with a cad. Though it be a good story to share.