Straight Gorilla glue, the small bottle! Even that's a near lifetime supply. Not sure of shelf life. The bottle I've been using seems to be getting pretty thick, is about 2 years old?

Hard to say how much I'm using. Not much. The stuff is REALLY thick, so you can't measure by the number of drops used? You could experiment with a slot cut in a piece of scrap?

I started by wiping the glue surface of the hinge across a wet sponge. Don't do that any more as I failed to see the benefit? Your results may vary.

I put the glue in the slot.

I've never seen it push a hinge out.

I will generally wipe any excess off with a paper towel right away. Then I wait for it to dry prior to any further cleanup.

I hate the unpredictable setting time with epoxy. This stuff seems much simpler, and seems to hold the hinges just as well.

Best of luck, -Al