Filler neck to trunk floor seal

I have been researching the attaching hardware for the seal around the filler neck inlet pipe to the trunk floor. AMK's kit includes pan head, gold cad finished phillips head screws. This has been confirmed on 1 mid-year production 73 original car.  An early year 73 production car has the same screw finished in phosphate and oil.  Two confirmed original 71 cars both an early and a mid year have hex head 5/16, phosphate and oil finish screws.  The attached picture is of the confirmed original 71 screws.

Dec '70 Metuchen built car, pan head phillips sheetmetal screws, don't remember if they were self tapping, but believe they are.

All of mine have pan head phillips and very short.