The housing is part of the TStat on the M112, and the IAT has no relation to the engine temperature.
186 deg with no A/C and 195 deg with A/C is normal for this engine, it will improve nothing to make it colder.
If cooler IAT is what you are looking for, go with a CAI ( Cold Air Induction ).
While it is true that the OEM setup is indeed a CAI itself, it is a huge heat sink sitting on top of the engine.
I have a single CAI and my IAT runs about 12 - 16 degrees above ambient cruising at 60 as measured by my UltraGauge.
I have noticed that the cooler the ambient is, the closer the IAT is to it.