Thread: best place to install water temp sending unit??????????

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I live in a place where 120 degree days are not uncommon at this time of year with little humidity. I'm continually told that outside temp plus 100 degrees is not unexpected on a modern car equipped with a thermostat,fan clutch, and/or thermostatically controlled electric fan....
Having said that, I'm usually able to get almost any of my chevies to run under 200 (160-180 at speed) with the following improvements:
1) A new 3 or 4 core radiator... cheap from Auto Zone or Checker
2) A new 160 or 180 degree stat.... be sure to heat water in a coffee cup to expected temp and test! I've been told that over 35 percent of new stats are bad!
3) Replace the fan clutch with a solid spacer, but keep the stock fan..... The sound it will make at speed will remind you of a helicopter or prop plane booting up for liftoff or like your trans may be slipping (it isn't). Folks say it will cost you horsepower and fuel mileage, but I haven't been able to prove the mileage loss thru careful testing. What I can gaurantee is reasonable temps and cold a/c even when idling at a drive-thru!
If you do those three things and your 454 still won't run cool, try replacing the water pump and completely removing the stat.
Once you get to this point the coolant will be circulating continuously without interruption. Auto parts guys are always trying to tell me that the coolant doesn't spend enough time in the radiator to cool, to which I reply that it spends comparatively less time in the engine being heated, as well. In practice, your engine will simply run cooler without a thermostat and you'll have one less potentially problematic part to ruin your day.... same for the fan spacer!
If you then are still running hot, you have cam timing, ignition timing, or carburetion issues, or are running too much compression or have bored the engine too big. Another thing to check when cold is if any of your cylinders blow antifreeze, which would indicate blown head gasket or something cracked.
To answer your sender question...
I really prefer to use the bungs in the intake manifold because the coolant present there is from both sides of the engine. An argument for using the head bungs is more accurate head temp with less possibility that the coolant level would ever be low enough to leave those locations high-and-dry. Many of the current manifolds have multiple bungs and I like to plumb in a mechanical temp gauge to verify the electric one.