I just did this re-rigging project after finding only three strands left on my 1x19 backstay cable at the Y-crimp. I doubled the crimp there since that was my point of worst fraying. In my research, copper crimps are recommended due to corrosion of aluminum with stainless. Keep an eye on corrosion if you are already done. I used a hydraulic crimper. The 1/8" die was way too small and made some nasty butterflys. I just picked the one that fit on my existing crimps and all went well. 3/4" Class 1120 PVC fits well for the turrnbuckle covers. I will be using a heat gun and a circular clamp or rope to pinch them down on the cabling at the top. I am thrifty so thinking of painting and reusing my shroud boots, or making them out of some thick vinyl. I sucked about 2 cubic feet of bird or rat nest out of my mast, scraped it, and am painting it with Rust-oleum marine metal primer (specifically recommended for aluminum) and topcoat. Once I rewire the mast with new lighting I will post some pics once done. I paid $80 for 500' of 316 1x19 1/8" wire rope, about $30 for the crimps, and $40 for the hydraulic crimper. I have enough rope to do another boat or two at this point and I think the last rope was from 1983 so I may sell it or help friends or find another project.
BTW...If anyone finds frayed SS wires anywhere, look close and you will see rust inside the rope all over the place. Replace it all asap. It is WAY better than losing the mast. My buddy spotted mine before I did and the more I looked the more I realized I was living on borrowed time. The hardware can last a lifetime. The rope needs replacing. Talk to anyone who has been dismasted.