Hello, I decided to replace my battery cables with a nice 2 gauge set and when I was disconnecting the positive from the starter I notice that the two other wires look brittle. I was going to replace the purple wire back to the harness and it has 10" of fuseable link do I need this much? or any at all there? It is spliced in real sloppy.Thanks.

Your call. Fusible links come in a fixed length so you use the whole thing. That's a 12 gage wire so a 16 gage link would be the proper size.
The 74 & 75 show a link on the purple wire while the 76 & 77 do not. I can't answer why they decided to start adding them in and then decided to take them out.

Thanks John, I guess I should have mentioned it is a 69 350 but I guess I will leave it in and just splice it in better.