Welcome! Glad you joined.
We were hoping for a bit more of an introduction of yourself and your truck. I take it from your "handle" that you are in Hawaii. Right? We have a map (Bullnose Forum/Member's Map in the menu) and we could add you with a city or zip.
And how about some other info? And pictures? We are a community and like to get to know each other.
As for your question, while we can try to answer it here, the best place for it is in the main section. That's because more people will see it there than here. But let's take a shot at it here. I am not familiar with the "pipe" you mentioned, but you should be able to install the engine coolant temp sensor anywhere that has a flow of coolant before the thermostat opens. So I do think you could install it in the intake manifold where the coolant passages are in the front or back.
Gary, AKA "Gary fellow":
Profile
Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI