This is kinda late for your effort, maybe relevant those that search this thread in future...

Given the PITA it is to change these switches, and like many parts they aren't what they used to be...
...the last one I put in I slathered with JB weld to give it additional leak resistance. My previous ones
had leaked between the steel nut and the plastic core. Hopefully JB weld will give me a few more miles.