I will warn ya, you dont want anything in the center under the turret above the original battery box level.
if i had this to do over again I would split my battery in half and put one set of cells as a stick down each side amd mount my ibu across where the battery door on the bottom is then the battery could be unplugged and charged in the tank from the bottom hatch, then put speaker up front. Everything i learned trying to arrange my 12v abrams the hard way.