Bill, just hack the Z32 up, and fit it to the piping.
Cut around the square box, leaving you with the electronics and the sensor sticking out.
Drill a large hole in your cooler piping, big enough to fit the sensor into.
Get some 2x30 ally plate (or similar), and make a 4-sided box to the size of the electronics box, and have them welded to the pipe. Youll have to contour 2 of the plates to suit the round pipe.
Then get some sikaflex, seal it up, and put some screws through the plates and into the afm. Might want to take the lid off to make sure you dont drill into the board inside.
Ive been running 22-23 psi through this and no dramas!
Illl see if I have a pic at home tonite.