70 Duster- Bench and bucket seat holes?

The holes are in the same location as yours. The metal has a ridge, for the reinforcing plates, but no plates. Think they drilled all floors for both configurations and welded the plates on in the assembly line?

Yeah the floor has a stamped recess to locate the reinforcing plates. I honestly thought I drilled the holes for the buckets on my Duster, I think the floor was dimpled where the holes were supposed to be and I drilled them out. But I can't remember clearly enough to say for sure that's what I did, and I didn't take any pictures showing the floor with the dimples and not the holes.

But that doesn't necessarily mean your car wasn't drilled for buckets at the factory. Could have been the order/options for the car was changed on the line, or that the worker tasked with adding the holes did an extra car that day by accident. Not unheard of at all, there are factory automatic transmission cars that left the factory with a z-bar reinforcing bracket welded in place on the frame rail for a 4-speed instead of just getting a rubber plug in the hole and no bracket. Like Alaskan_TA said, if you can look at the fender tag or build sheet it would tell you if the car came with buckets or a bench.

the bucket seat holes are not drilled on bench seat cars

Yeah I think that's right, I think the floors were dimpled at the locations the holes were supposed to be for the bucket mounts but not drilled. There are a bunch of places where that was done, the parts were stamped with dimples for the locations of optional holes and the holes were drilled later if that option was going to be on that car.

For example, you can see the dimples in the floor where the auto floor shifter would have been located in this picture. My car was a column shift so the floor shifter wasn't added. (I was adding a 4-speed hump).
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