Trunk Floor Extension Help

[Gary AAR]

I need to correct an issue with the RH trunk floor extension in my 1970 Cuda.  Issue is the extension did not come with the large oval slot that the fuel vent lines pass through.  So I need to add the oval slot and the (3) mounting screw holes that are used to attach the cover plate.  I can use the cover plate as a template to locate the (3) mounting screw holes, and I have the foam gasket for the cover plate that has the oval slot cut out.  The approximate size of the oval slot in the foam gasket is 2.00" x 3.50".  Would anyone have a trunk extension to measure to confirm the oval slot size?  Then I also need a couple of dimensions to properly locate the position of the oval slot in the trunk extension.  There are a couple of formed bend lines in the trunk extension that are 90 degrees from each other.  Could anyone give me the two dimensions from the bend lines to the edge of the oval slot?  See pictures below that show a scale measuring from the bend lines to the edge of the oval slot that I'm looking for.
Thanks in advance for the help.

[DeathProofCuda]

This is what I got from looking at my car, 70 Cuda.  As the rot in the photos indicate, this is the factory original trunk extension.  Keep in mind that with the tank vent lines in place, trying to get accurate measurements of this is kind of a b!tch.  Sorry, I wasn't about the take the thing apart to get better measurements of the hole location.  I had to make some of the measurements from the underside of the car to see the actual metal edge of the oval slot, since it is covered by the gasket up top.

As I measured it, the oval slot is 2" x 4".  The trunk extension looks to be 7" wide and oval slot looks to be centered along the center line of the trunk extension.  Therefore, you should have about 2.5" on either side (left and right) of the oval slot.  As the photo 1 shows, the vent lines running through the center of the slot hit right about midway (3.5") between the left and right edges of the trunk extension.

For fore to aft placement of the slot I measured from underneath the car from the front edge of the truck extension (where it is welded to the wheel house).  The front edge of the slot is 1.5" from the front flange on the truck extension. 

Photo 2 is probably less helpful, but gives you an idea of where the foam gasket should hit relative to the rear edge of the flat spot on the trunk extension where the oval slot comes through.

Let me know if you need me to clarify any of my ramblings...

[DeathProofCuda]

Here are a couple more photos from the top with the gasket partially removed. 

Slot is definitely 2"x4". 
Right edge of slot is 2.5" from right side of drop off. 
Rear edge of slot is 1' from where the flat spot drops down in the back.

[Gary AAR]

Thanks for the response and pictures.  That's the info I needed!