Mark is right, the top of the filter housing is the best place. Be careful where you route the wires,the exhaust manifold and turbo area can get wire melting hot. Also make sure the wiring won't be in the way for changing the oil filter. I removed my oil temp gauge and reinstalled it on the intake manifold,the oil temp was a boring gauge, got to 180° and pretty much stayed there. Intake air temp is much more interesting,but your gauge will need to read down to about 50°,mine reads 0°-350°. My gauge is switched between two senders,the other is for AT temp.
------------------
95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)
------------------
95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)