Followup Note: Ending up with disconnected HDD thermal sensors due to breakage apparently causes the main system fan to run at full speed all the time. This is extremely loud and pretty much defeats the purpose of the Mini form factor. Going to have to try to rig something up with actual solder or adhesive tape.
This is just stupid. A computer where logic board connections get broken while replacing a frickin HDD. All in an attempt to do something about the pathetic and feeble hard disk the vendor includes with their crap hardware (50MB/s transfer--what is this 1998?). Last Mac Mini I will ever buy. Slow, yet expensive and fragile.
BEWARE! Gently pulling one thermal sensor wire up from its logic board connector caused wire to rip loose from connector, leaving connector still in logic board socket. Using spudger on other connector caused same result. Even after wires ripped lose, it was impossible to get connector out of logic board socket (using spudger and needle nose pliers the connector came away in pieces). Connectors almost seem glued/fused into sockets and the wires will apparently break lose before the connector will release. What a terrible design. Here's hoping the mini will run without HDD thermal sensors :( I am experienced with repairing laptops and am kind of ticked because I am sure this damage was not due to incorrect/rough handling during attempt to disassemble.