Stay safe with Big Orange - can you get him some toys he has to hunt and 'skin' and perhaps lick..
I think there are some around but probably horribly expensive.
I've used the lickimats made for dogs, for cats - just spread some suitably tasty lickable stuff (I think you can get paste cat treats, I am not so familiar with cat treats as I am dog ones)... the UFO type lickimat (robust, has suction pads on the back) can be stuck to a smooth hard surface which can let you stick it to some interesting locations to get him moving around and doing, distracting him from self harm.
Small juice bottles (errrrrrr Tropicana the tiny size you get in meal deals or used to) - take off the lid, keep that to one side. Remove the ring from the neck - clean and dry and then pop treats/dry food in and let him batter it around to get the food out.
Next level of difficulty is to make some small holes in the bottle but put the lid on, so its harder to get the food out.
Final difficulty level - get some tiny itty bitty kids socks, pop the treat filled bottle into a sock, so now he has to 'skin' it to get the bottle out, then get food out of the bottle.
You can then make several of these and place them around your house for him to hunt.
Providing outlets for natural behaviours can help calm and distract, and direct his furry brain weasels into something productive.