So I've encountered a few regs who open and 4bet quite exploitatively from the button versus the blinds. Many of them are opening about 50% OTB and 4betting 20% of the time.

I've started to get the ball rolling with math and ranges with what little I know about theory but would appreciate some advice on how to find the 'equity theshhold' so that I can crosscheck individual hands in my 3bet range to this 'equity theshhold' and, if they have equal or higher equity than needed I can 5bet jam them. I'm at a bit of a stand still at the moment but here's what I have so far....

Villain opens OTB 50% of hands.
Villain 4bets 20% of time.
Villain calls the 5bet jam with 4% of hands [AA-TT,AK] or 12.5% of opening range.

Since villain 4bets 20% of the time and 4% of his hands are for value, villain is 4bet bluffing 16% of the time
or a 4:1 bluff:value ratio. So villain will fold to a jam 80% of the time he 4bets and call 20%.

2/4 game:
Opens OTB to $8, hero 3bets to $32 from SB, BB folds, vilain 4bets to $78.

Assuming hero plays a 5bet/fold strategy OOP, villain risks $70 to win $32+8+4+70 with his bluffs.
$70/114=61%.
Villain breaks even 4betting ATC if hero folds 61% of the time and loses money if hero jams more than 39% of the time.

Assume hero 3bets 15% from the SB vs villain's button open 77+, A2s+, KTs+, QTs+, J9s+, T8s+, 97s+, 87s, ATo+, KQo].

In a vaacuum without villain adjusting yet, what range can hero profitably 5bet jam vs villain's 4bets?