"Will this make Trump's base angry?"
They're always angry. The "fuck your feelings" crowd is always angry, yes. So who cares if the FBI and DOJ do something to make them mad. Screw their grievance.
If he or any of his cronies broke laws, hold them accountable. I will say the exact same for Hunter Biden, who has never held office and or worked in the West Wing of The White House. Apart from that, I don't give a shit who feels the need to feel fake outrage and victimhood over having to follow the damn rules. Piss on all of them and let them cry about it.