For those of us that like the look of having a key in a bar end cap but find that it sticks in to everything when in your pocket, here is an alternative option.
Here's what you need.
Put the key in your ignition and press it in and turn to the park position and mark the key.
Measure the depth of the hollow inside the end cap and mark the key to where you will cut it off.
Put a dot in 45 degrees from a corner. this is where it will pivot.
Cut the key and round the outer corners.
Drill a hole big enough for your pivot shaft to fit through. I am using a small nail which I have cut down.
Cut a slot in the cap to hold your pivot shaft and check for positioning.
Cut the slot to the side to hold the key when folded down.
Glue in the ends of the pivot shaft first. When dry test that it moves as expected.
When satisfied, put something in behind the key to make the slot when the glue is poured in.
I used some cardboard and used a barrier cream over it and the key to stop the glue sticking to it.
You can use vaseline or anything else really to stop the glue sticking.