1966 Coupe to Fastback Conversion

Hi everyone! I have a ‘66 Mustang coupe and am considering a fastback conversion. I’ve already found most of the Dynacorn body panels fairly easily, but I’m wondering how challenging it is to track down the other fastback-specific parts, like the louvers, seats, and other components. Has anyone here tackled this kind of project before? I’d love to hear your experiences and advice!