100mcg Fent patch dosage

Using a throw away for personal reasons. Looking for a decently timed response: I have been off opiates for 3 years but have a 100mch Fent patch on hand for a treat. I plan to put a piece on my gums. What’s a safe place to start for dosage? I cut it into 20 and then cut one of those 20s in half so I essentially have 1/40th loaded up. I am not alone and have narcan on hand but my partner and I want to take them “stacked” because we are going in blind about safeness. Been over a decade since either of us took them and they were different back then. I’ve been scouring threads for the last 2 hours and see conflicting recommendations some say 20 while some say 64 sooooo

Help.