Pegleg, after looking at some of the sites I can see where some confusion would set in. Ford listed one for your application. 71 Grandé, "H" 351 with FMX was D1ZZ-17290-G, R/B D4FZ-17260-A. Original cable was 61 1/2", the replacement was 67". I would check with Don (OMS) to get an honest opinion on the ones offered now and how close they are to the original as to the length and how well they fit. The same cable was used on some model Pinto's and Maverick's so availability should be good.
Also let me know what you decided on your trunk mat. I may have something to help you with that.