I am building a 1967 convertible ... literally from the ground up. Right now I am doing all of my planning work (I hate getting halfway into a project and then realize I inadvertently missed something and must go back. Hate it, hate it, hate it). My wife has MS and there are certain things for which I must make accommodation if I want her to enjoy the vehicle as much as I will. Two of those things are 3-point, modern seat/shoulder belts and headrests; two things that were not available in 1967. Does anybody have any suggestion on how I can procure/customize/etc. such parts? Thanks!