Need help:Temp sender installation 175HP V6

[joe28704]

I looking for some help in the proper installation of a temp sender(12415) and Cover(12419T) in a 1985 175HP Engine (ser#6619329).
I have a ton of questions. One big one is is this intallation DRY?, Installed like the temp sender/switch on the starboard head (for alarm)or is drilling thru the cylinder cover(at sender well, port) to expose the sender to water and then seal sender cover to cylinder cover?
The sender cover and sender both have 1/8 NPT threads, (this "hints" at a "wet" installation of sender.)
I did not order part#19-12431T because it's description is "Plug" and I figured it was used to plug the hole in the Cylinder head if temp sender had to come out once hole was put into cylinder cover. My port cylinder cover has no hole in it at this time.
Thank you

[boats.net]

Use grease or anti-sieze on threads and install it like temp switch on other head.

[joe28704]

This sensor (port)does not even remotely look or function like the sensor/switch feeding the alarm("other head"). It cannot possibly be installed like the starboard head one.( A look at the parts diagram demonstrates this.)
By the way, the "plug" seems to be made out of aluminum from a picture of one on E-bay, it does not seem to be used to "seal" anything maybe its a heat conductor of some sort. I have placed an order for it as this seems to be a necessary part of the installation. Having it in my hands may yield more clues as to its use/function.
Has anyone actually used this sensor/cover/plug combination to install a temp gauge?
Thank you.