[sidewaysinthird]

There are always a few things that can be overlooked when something that seems so simple. With that in mind and just a guess from someone else who isn't looking under your hood like you are: The digital meter you are using to check the water temp is in the _____ and the actual temp sender for the gauge is located? With the fan running the radiator temp may stay fairly constant and the sender if located in the either the head or on top of the manifold may show the actual temp. The other guys are correct about the lights being on causing a voltage drop which could slow the fan speed, but it can also slow the idle speed. However just the 100rpm or so drop from a 60amp alt at full charge doesn't seem enough to cause a reduced water flow enough to cause such a rise in water temp. Another guess might be to check as was said before all the grounds for the fan and the dash panel. Just to ensure less of a voltage drop with the lights on you could hook a second battery via jumper cables and see if the gauges give the same reading.

Like I said these are such simple little things which of course makes them very difficult to hunt down. Just my thoughts. Best of luck.

Mike