Update:
I am transitioning from the cabin to the front clip area on my post paint rebuild. This does not include aesthetic improvements that I will be making later, after the car is registered and on the road. The year at the paint shop has clearly pointed out all of the parts that need to be removed and powder coated. All of the suspension links, half shaft adapters, sway bars and a number of other bits that look sorely out of place with their new orangish patina

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I am very pleased with the Ford Motorsports sill plates that I installed. Although they were made for '70/'80 Ford F150s, they really add a nice touch to the sills with the FMS logo and provide something for the weatherstripping along the bottom of the door to seal against. I had to build the sill up 7/16" to accomodate the lip on the polished SS sill plates. To do this, I found an inexpensive material that is readily available. It is 1/16" thick and comes in 4'x8' sheets and is a fiberglass/polyester composite used for lining bathroom walls inexpensively. (You'll probably want the flat stuff, not the textured variety

It is very easy to mill/shape and can, obviously, be laminated to provide most any thickness. Its flexibility made it very easy to fit into place while having lips that went under 'in place' parts. Two narrower strips along the outside edge also provided a nice pocket for the carpeting to go under the edge of the sill plates while providing a stable base for them when they are bonded into place.
I was agonizing over a seal from the sill plate up to the windshield and just behind the door hinge; should it be metal, composite, or what?? I was in the process of shaping pieces of my composite sheet to laminate, when my neighbor brought over a piece of high density, closed cell ?latex? foam that he had used as tie down fenders on his boat (where rope went over the edges.) He told me that with all of the squishing and rubbing that the ropes inflict on the stuff, it always bounces back and shows virtually no marks. So using the templates I had created for this space (took ~5 to get it to perfectly profile the shape of the inner door just behind the hinge) I carved a couple of pieces from 2" thick blocks using an electric carving knife. The supplier only had this stuff in white, but the new "plastic" paints seem to have enough flexibility to allow them to deform without the paint chipping off. (Time will tell the full story on this.) The foam is stiff enough and there is enough profile variation under the edge of the dash that I have not had to bond or mechanically attach the "seals" at this point. They obviously do a great job of sealing this space, which will otherwise duct air, and whatever it's carrying, from the front wheel wells directly into the cabin.
Regards,
Lynn