@Moriarity Mike McConnell, the car was referred to as "Big Booty Judy" don't know if that's what it's actually called or if someone just referred to it that way... ....
I DO NOT KNOW if this is the car, but my father (Dee Wescott) talked about customizing a Plymouth into a 3 window. The story was the customer was a fluorescent light bulb salesman who delivered product from his car. He had several 3 windows in the 1930's that he wore out and when WW2 ended he wanted a new car. As 3 windows were no longer produced the car went from showroom to being customized. My father did not know of what happened to the car after the 1950's.
That is a 49 Plymouth business coupe and not a modified body. Very few mods and the only actual one I see is the removal of the Plymouth letters on the hood. With all the trim and the goofy and ugly hoods over the headlights I am saying that it has been a Bomb Lowrider and not a custom. No body mods and no chrome removal is bomba lowrider and not custom. That is probably why none of us long time custom car/rodders in the PNW know the car. It didn't go to normal Hot rod/custom car events in the PNW as you didn't and still don't see a lot of lowriders at most rod/custom events except fully open events. They have their own events that draw big crowds and are damned expensive to enter or go to normally. this is a pretty well stone stock 49 business coupe.