Are you actually trying to modify an AirPort Extreme to hold a hard drive? It sounds like it. You lost the sata ribbon and rubber plate and metal plate for a 2013 Time Capsule? Sounds a little strange. How do you lose all that? Can't help you with those parts I'm sorry but if you are looking to get them to try the Extreme mod then think twice as the logic board does not even have a point to plug the sata ribbon/cable into. Just thought I would mention that. Apologies if I am misreading your post.
I upgraded the HDD in my 2013 2TB Time Capsule to a 4TB. It is possible as iFixit says but about the same level of difficulty as a hard drive replacement in a Mac mini if you have done that. You will need some very thin spudgers to get the base off. Also there are a few thin wire connectors that are not for the faint hearted. Drive used: Seagate Barracuda 4TB 7200rpm (ST4000DX000). It is a hot running drive ordinarily but does not appear to heat the TC up (any different to what the 2TB did). Even with doing the initial backup of 5 Macs at once it did not get too hot. I am guessing the writing speed is not challenging for it, or the internal fan is efficient in moving the hot air from the top down out the vents in the base. A few tips worth noting: 1. Find a very thin plastic, but stiff, spudger to get the base of. Two or more would help. The black base is a soft plastic and is marked easy. A thin spudger shouldn't leave any marks. 2. You need a torx kit. 8 from memory. 3. Connectors are very delicate. I...
I am not sure what you would gain from the SSD apart from its low temps. There would be no speed advantage as you would be operating through ethernet at best. A quality HDD would easily saturate that bandwidth. There is a major issue with how it would be mounted though. The TC does not have traditional mounting points. The HDD is held in with rubber corners and a 'pressure' plate holding it all in. Even if you get a caddy it will likely not fit. Basically you need a standard HDD 'shape'. Also the TC spins the drive down when not in use. I am wondering if this would possibly cause problems with an SSD.
I am late on this post but thought I’d reply. You need to break the fusion drive in Terminal. Terminal commands (the rights ones) will remove the coreStorage setup and the drives will appear seperate. There are plenty of tutorials. Type how to split or break a fusion drive in a search. It is similar to building it in Terminal. It is done from a USB boot drive. It is not hard if you follow instructions and get the command right.
I am late on this post but thought I’d reply. You need to break the fusion drive in Terminal. Terminal commands (the rights ones) will remove the coreStorage setup and the drives will appear seperate. There are plenty of tutorials. Type how to split or break a fusion drive in a search. It is similar to building it in Terminal. It is done from a USB boot drive. It is not hard if you follow instructions and get the command right.