6X9 Speaker Box Ideas?

[72step]

I currently have a pair of 6x9 alpine speakers in 6x9 speaker boxes. For some odd reason the seat I have now doesn't allow them to fit lying on their side, and my old seat did. They're both stock 67-72 chevy truck seats--who knows?, but anyway my current seat doesn't have enough room. What ideas do you all have, as I refuse to cut the truck in any way, and I have a behind the seat gas tank. I really didn't want to mess with the speaker boxes either because they're nicely carpeted. Currently I just have them face up right on front of the seat. They sound great there, but they can be bothersome to your feet. Thanks in advance to any and all advice.