joemikeb will probably direct you to OWC for professional service, and after looking at
Mac Mini Late 2012 Hard Drive Replacement - iFixit, I can see why.
More amazing to me than the way some of these machines are put together is the design effort that must have gone into making them that way.
It kinda reminds me of when my daughter moved back to Brooklyn from Toronto and I unloaded the U-Haul that she had loaded; I had to stop more than once and say to myself "She put it together, so I've GOT to be able to take it apart."
As far as SSDs go, upgrading my MBP was almost life-changing. You won't regret whatever it costs.