Is no RTV silicon? IT should stick but not as well as I wuld like
IF you remove the cover from your A/C (Outer cover) you should be able to find the "Drip Spout" on the water tray.
you can, if you wish, put a collection "Cup" below it and tubing to the spot you want it to drip down. One possible pate is down the vent stack to the wet bay and from ther around the tanks to ground This is a nice path to take.
ISSUE Tubing can clog due to algae growth.
Optional is to put a channel (More on this in a bit) layed on the roof to a "Drip point"
I would take a square PVC Tube. Cap the end that slides under the LIP. then attach it to the roof with DiCore non-self leveling caulk You might also use screws (Caulked) with a "J" type hook to hold it (Do not put the screws in the bottom of the channel)
Literally an "Aqueduct" system.
That said. I would not do either.
Home is where I park it!