Sounds like something is missing to me.

Here are some pics that show the seat mounting in my '51. First is the riser that's welded to the floor with the seat adjuster rails bolted to the riser. Then pics of the seat bottom springs and the seat back, both from the back side. They fit into the seat frame that bolts to the adjusters. Then a picture of the Factory Assembly Manual page (Section 1, Sheet 2.00) showing the seat frame. The factory upholstery doesn't go under the seat springs.
Attachments
IMG_0416.JPG (268.36 KB, 124 downloads)
SEAT RISER AND ADJUSTERS
IMG_0425.JPG (311.19 KB, 124 downloads)
SEAT BOTTOM SPRINGS
IMG_0427.JPG (345.71 KB, 126 downloads)
SEAT BACK SPRINGS
IMG_5983.JPG (329.04 KB, 126 downloads)
SEAT FRAME PAGE


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.