You don't have to unplug, replug, disconnect, reconnect or worry about series or parallel. Give analog meters a miss. A needle is nowhere near as clear as LCD numbers. I place the naked panel, the multimeter and a 12 volt battery on a table and connected them in simple series. It's exactly the same as when you turn on a hot water tap in your house.
Water runs out of the tank.
Water runs into the tank, registering on your front yard meter, and water runs out of the dam miles away. The only difference in this case is that the dam is not miles away. We are surrounded by it - a vast ocean of electricity in which the Earth continually floats. Being aware that any light, natural or artificial, produces the photovoltaic effect, I decided to use a flourescent tube as the light source. The light would now bathe the naked panel.