Stretched over several days, but determined today that all the fettling had been effective:
Remote sender for motorized garage door stopped working.
Since the LED wasn't illuminating, decided to look at the battery.
Snap-on terminals for the 9V battery were corroded.
Pulled the terminal holder off of the battery; one connector broke.
Researched purchase cost of a new remote.
Spouse made executive decision, directing repair, not replacement.
By and by visited the local "they have everything" hardware store and a couple of the staff remembered where in the electrical bits department that replacement battery connectors could be found.
Also purchased some squeeze-on wire connectors to attach new, skinny wires to portion of old, skinny wires.
Set about stripping insulation from remaining part of old, skinny wires.
Succeeded in stripping the first one.
While stripping the second, pulled it off of the printed circuit board.
After a day or two, remembered where my soldering iron was, and retrieved it.
Heated up the solder blobs and extracted the remains of the old, skinny wires.
Inserted new, skinny wires through the holes in the circuit board, and successfully soldered them, without compromising other circuit traces.
Located the household supply of 9V batteries.
Tried each of them. They were flat, and about 2-years past the "good until" date.
Purchased more batteries. Noticed that package now boasts about 5-year life; used to be 10.
Installed one of the new batteries. Reassembled the snap-together case.
Pushed the button.
Watched the door open.