'53 Skylark Interior Part Identification Help

[53Skylark]

Can any of you familiar with the '53 Skylark or '53 Roadmaster Convertible give me an idea of where this interior trim piece pictured below goes?
I inherited the car from my father, and it was originally my grandfather's. My dad had a Rubbermaid bin full of spare parts, most of which are easily identifiable (extra interior door handles, emblems, spinners, etc). This piece was in among them and I have searched throughout the car and cannot determine where it belongs. Searching through pics of car interiors online didn't help. It is just a piece of steel with the vinyl covering on it. I'm sure it belongs to the Buick as the interior is red and white and perfectly matches the rest of the yellowed white vinyl. Thanks in advance!

 

[TODD]

Could you give the dimensions of it?

And show a side view unless it is a flat piece?

 

[53Skylark]

It is 14.5” long and 3.25” wide and is not flat. It is concave through the center so the top and bottom edges are higher than the center. You can get an idea of the overall shape from the far left edge of the photo. The screw holes are spaced 4.75” apart and 2.25” from the edges. I can’t find anywhere in the car that lines up with them. If it wasn’t for the perfect color match with the rest of the car interior, I would doubt it belonged with the car.

 

[TODD]

This is a wild guess. See attached exploded parts view of the hydraulic seat adjuster assy. Part AF is a cover for the mechanism. Shop manuals indicate this cover attaches to the front of the seat frame.

 

[53Skylark]

That certainly looks like it. Thanks a bunch!