I managed to get the tonearm wire clips off of the cartridge pins and have removed the old cartridge; still waiting for the new one, but that is progress!
The clips were on the pins pretty tightly so it was scarey, but I didn't damage the wires, and the boots are still intact. I was able to push back the boot on one of the wires far enough to see what the clips looked like so I could grasp each of them in the right place with a pair of needle nose pliers. Whew! Glad that part is done - I definitely don't like messing with those little fragile wires!
When I get the new cartridge, I will clean the tonearm wire clips and the cartridge pins, even though the cartridge is new. I am sure putting the clips back on the pins will be relatively easy; I can always loosen up the clips with a toothpick so they slide right on and then tighten them down a bit - very gently - with the pliers.
Thank you again for all of your help, everyone. This newbie very much appreciated the hand-holding!
Holly