I haven't looked at the av seat, but if it's like most manual seats, there will be a series of notches in the part of the seat where it pivots, probably has a stud or something similar to stop the movement, it would have to be removed, then additional notches made to latch in the needed position, as others have said, the reason for the stop is so that the seatbelt is still in an affective location, won't do much good in an accident if driven this way, you'd slide under it.