My apologies for derailing the thread, the "Lone Star" reference peaked my curiosity. I do hope, like Jeff mentioned, that you and your son continue to source information to help you with the best decisions possible to achieve your desired results (such as your requested driveshaft markings).
Perhaps, if you choose to, begin a Member's Build/Restoration thread on your unique car. I would thoroughly enjoy watching and participating with your progress as you seek out the finer details of your car.
For the last +40 years, the one common thing I always heard when (even myself) discovered that "Oh, it's ONLY a Coupe", that the nay-Sayers always said "It's not worth anything, so why bother". Well, for me (and it sounds like also for you and your twin brother), it was my "FIRST Car" and for my first car, I wanted something I could enjoy driving for a season and then to one day restore it to it's original glory of "new", in my later years, to after enjoying it again for another season in retirement, to hand down as a legacy of sorts to my offspring. For ME anyways, that makes it worth it to hunt down such details to restore my "It's ONLY a Coupe" car. My project being a mere "labor of love" for all of these now 41-years.