I did this - bit of a pain to get to it - need to unbolt the AC compressor and pull it down out of the way (no need to remove any lines to the compressor) and access the pressure sender from underneath the car. Even then it's tight. Sorry, I can't recall the thread size or the diameter of the fitting. I ended up putting in a reducing fitting that then went to brake line which I snaked up to just next to the handle on the dipstick - T'd it there and put old pressure sender on one side and new pressure sender on other.
Eric