Resource Guarding Puppy - advice & positive stories please

Our little boy is just 11 weeks and already resource guarding - he growls, snarls and will bite if you come near his food bowl, kong or something he's stolen ie. socks etc

To help train him out of this, we have been diligent with the following, but any further advice or positive outcome stories please share as I'm very concerned that he won't train out of this 🥺

Feeding: Breakfast - hand feed doing training (sit, stay, drop, leave it) Dinner - in bowl, put half food in bowl and then continually approach his bowl while he eats and drop in more and more of his food

Stolen Items he can't have: When he takes an item (sock, shoe, tissues etc) I walk near him and say 'trip' and drop super high value treats near but away from him (cheese) so he walks over to eat the cheese and I'll remove the item when he's not looking

His toys & high value items of his (kong etc) I got up to him when he has it and do the trade technique, giving him some treats and patting him but not removing his toy / kong - so he knows me approaching him doesn't mean it gets taken away, instead he's getting more treats