Well I dont think the sides of our X5's are totally sealed where the OEM amp is on the left side and on the right side where the fuses are. I assume that chamber will and could act as an isolated chamber for infinate baffle subs. I would be willng to try if I could find a set of used covers to cut into. I am sure I could mount from the back side fiberglass a grill cover and re-carpet that cover in acustically transparent carpet to match the OEM carpet