Got it working right as I was getting ready to turn in for the evening.
For some STUPID reason, I hadn't noticed there is a power cord and switch on the back of the 1020! Plugged it in and turned it on and suddenly, I had a 5.25" drive!
Wasn't even looking for it since all the external drives I've ever used on the Amiga were powered by the cable.
Separate power cable! Sheesh!
Makes me feel like an absolute rookie.