There are 3 temp sender/switches on the intake...
1) hi-temp fan overide switch (top of intake, behind AC compressor),
2) temp sensor for data to the ecm (front of intake, on the rite looking from the front), and
3) 'hot' idiot lite temp switch (front of intake, directly to the left of the upper rad hose)... you can use this one for a gage sender location (adapter may be required) but of course you lose the idiot lite functionality... this is where my mech. temp gage sender is installed... some people 't' a gage sensor in here also, so as to retain the idiot lite, but it's kinda cheesy with a 't' connection and not that easy to fit it all in there as I recall...
I'm pretty sure the previous poster is correct about there being a tapped location on the side of the block as well... contains a pipe plug... you could use that also, but I think the location at the left front of the intake is a better place to take the measurement.... and so did the gm engineers... hope that helps...:wink:
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