How do you handle a dog that resource guards toys but not food?

My 3 year old pit mix is fine with his food bowl. You can take it away, add food, whatever. No issues at all.

But toys? Different story. He growls if another dog even looks at his ball. Snapped at my roommates dog last week over a squeaky toy. Nobody got hurt but it scared us.

Everything I read about resource guarding talks about food. How do you address it when its specifically toys? Do I just remove all toys when both dogs are out?