Got a 440 in my Charger and am curious if I can snake the oil pump out without dumping the oil. All or most of the oil is in the pan correct? Cars been sitting awhile so i figured it was bled back and the pump should come without too much mess?? Or should I dump the oil first? Cars oil pressure is fluctuating and I am gonna swap pumps and see if I can bump it up a bit and get it more consistent.