Parts worked fine. Afterwards, software troubles abound.
I had a 250GB SSD as ordered from Apple. Needed more space. Decided to add a Crucial 1TB drive in the bottom bay.
I had bought another drive cable online and it didn't work at all. Sorry I didn't go with IFixIt. The IFixIt cable worked perfectly. Now if I could only get the Mac (Disk Utility) to build the new SSD from the BU Time Machine. Keeps failing. I tried reboot with Option/Cmd/R and just Cmd/R to try and rebuild but nothing is working so far. I will continue the quest to slay the dragon.
Go with IFix IT in the first place. Get what you pay for. Something that works and lots of advice online.