Do I need to remove the battery cable clamps (left, right or both) from the battery upright post before charging the battery? [This car is rarely driven, and so the battery needs attention quite often]
No. You can leave the cables connected.
You may want to invest in a battery “tender” if you can park your car where you can reach a plug. Chargers are designed to charge a low battery, but most, including the “automatic” ones do a poor job of keeping a battery charged. For that you need a battery tender. The one I just bought cost me about $20.00 and will charge a battery (very slowly) and more important, it will keep it charged without overcharging it. It just keeps checking and when it sees the battery going down a little, it goes back into charge mode.
THANK YOU for the “battery tender” recommendation! I will definitely be purchasing one!