One note about the stock style of thermostat installation. They tend to push up and turn then do nothing. I keep mine down with a single strand of stranded wire through the stat, down the neck, and under the hose. (Be sure to remove the rubber gasket that comes on the Stant stat as it just rolls off when the hose is pushed on and causes trouble.) Also, there is no vent hole to let air through when filling so I drilled a 1/16" hole for that. Does not affect it's function.
Others put a second hose clamp just above the stat to hold it down which is fine if you don't care about the looks.