Just scrolling through kijiji, and found this car. Looked really good, but unfortunate what happened. You can see before and after pictures in the listing. But What would start or cause a fire like this?

https://www.kijiji.ca/v-classic-cars/oakville-halton-region/salvage-parts-car-1969-buick-riviera/1693488003

Requiem for a Heavyweight...

Perhaps a fuel leak somewhere. I wonder if it had an electrical hack job for a killer stereo?

Most fires in GM's in car from 60s to early 80's started in the cowl area. The wiper motor was the culprit on a high percentage of these. This area in the middle of the cowl behind the carb and distributor was where most started. It was also where GM routed wires thru the firewall on a number of models. Driving down the road the fire would start in the wiring and then forward movement of the vehicle would force the fire inside burning along the wiring harness, melting the plastic (or wire reinforced mesh) HVAC ducting and then up the defroster on to the windshield...