You might just have to dedicate a day to triceps/delts. My favorites are rear delt fly, skull crusher and dips.

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For rear delts spam reverse flys machine and face pulls, for tris definitely do compounds like bench or dips but for isolation cable push downs and extensions have treated me well, I’d recommend skullcrushers also but weird if you not feeling it, maybe try to go down some weight, widen grip, and focus on pushing elbows together throughout the motion

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