Welcome to the forum.
I had looked at that car previously seems to have some great options and looks to be a solid car.
You asked about going to the deluxe interior. The biggest difference is the arm rest and the inside door handle and mechanism. I think you have to replace some of that. Also the deluxe steering wheel has different center or a three spoke rim blow.
In 72 & 73 you got the deluxe interior in all convertibles I think.
The other barrier you will have is getting the comfort weave seat covers. They do not make them just fake printed comfort weave. Last time I checked with SMS upholstery they were out of the real comfort weave material.
You already have the convenience group looks like so door panels and seats are the only changes you would be making.
The repo door panels do not come with any of the trim so you will need to locate donor panels but coupe, vert and fastback are all the same.
The top will need replacing soon but can fix the hole from the back side also. Kee tops in Charlotte, N.C. makes really nice tops.
When you do the top there will probably be rust in the rain gutter around the back that will need some attention.
Also when the top is off be sure to go through the front latches and rebuilt / repair. You cannot get them apart with the top on so do while it is off. If you can locate another frame you can actually rebuild the entire frame and just swap them out.
I preach to the forum about never washing these cars with running water or car wash. You just feed the rust inside the doors, quarters and cowl when you do. Just wiping with wet microfiber towels will do fine and not keep the rust alive.
The inside back panels do not have speaker holes either. They are impossible to find and 71 is a one year thing also. You have the door speakers and the grills for 71 are also a one year thing. One center bar on the back side 72 & 3 had two or three I forget.
I have 5 of them sitting around here.
