Step 1: Barrier
Air line for a fish bubbler. I just cut a small section and placed it under the fine pieces of metal that press down on the sensor. by
You can stop here if you want. The sensors will not depress nor will the hot shoe mount be able to go in far enough to contact the sensors disabling the flash popup. Just keep in mind that your defuser can come out and you may not see it drop leaving it behind. $20.00 down the drain.
Step 2: Drill
Then I drilled a hole on each side of the diffuser arms.