Wayne Parham Messages: 18792 Registered: January 2001
Illuminati (33rd Degree)
I wouldn't modify the mains because too much rides on their dimensions. You could modify the subs but I think they might still be too large.
I think it might be best to look for a smaller subwoofer cabinet. I'll bet you can find a high-quality small sub that will work well. It would trade some efficiency for size, so you'll need a little more power, but that's OK. It's just physics.