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 There is not sufficient coolent flow across some parts of the intake manifold to properly actuate a gauge.  I am speaking to the rear driver side threaded plug specifically.  I am using a GT40 upper and lower, but I would guess this is true on many 5.0 manifolds.  There should be a boss in the thermostat housing that can serve as a good coolant sender mounting point. To use it: remove the housing, drill, tap, add a bit of silicone sealant and you're all set.  If you are using an electrical sender, go a little lighter on the silicone to insure a good ground.  I used this sender mounting poitn and grounded my autometer gauge on one of the housing retaining bolts and it works great. |