normal will vary between trucks on these ol gauges Jon, might be anything from say 1/4 to 1/2 or a bit above, and it depends on the rating of the stat, 160 or 180 etc - what's best is to warm it up and check the temp in the rad and compare to what's on the gauge so you know that particular trucks "habits" ... you might be able to see movement, but don't panic if you can't really tell, there's a baffle in the top tank - the temp is what matters, and an infrared thermometer is useful as you can check the temp on both sides of the thermosat at the housing, the temp of the top and bottom hoses, etc
Bill
