I dont know what the mount depth is for the woofer but from various sites such as
http://www.justforjeeps.comhave it as a 6 1/2 inch woofer. This may be a viable replacement, and way more sturdy. How are those subwoofers anyway? Are they worth the money? I was thinking of getting one to add a little something to the speakers!
Subwoofer Specifications
Subwoofer Series CompVT (CVT)
Subwoofer Size 6-1/2" Peak Power Handling 300 watts
RMS Power Handling 150 watts
Voice Coil(s) Single
Impedance (Per Voice Coil) 2 ohms Frequency Response 25 - 350 Hz
Sensitivity N/A
Xmax (millimeters) N/A
Subwoofer Design Round / Circle
Main Cone Color Dark Gray
Woofer Composition SoloKön
Woofer Surround Santoprene Rubber
Subwoofer Grille No
Re-Cone Kit Available No
Recommended Enclosure Specifications
Recommended Enclosure Type Sealed
Minimum Sealed Box Volume 0.2 cubic feet Maximum Sealed Box Volume 3.0 cubic feet
Minimum Ported Box Volume N/A
Maximum Ported Box Volume N/A
Top-Mount Depth 2-7/8"
Cutout Diameter 5-9/16" Shallow Mount Installation Yes
Warranty and Return Policy
Return Policy Standard Return Policy
Parts Warranty Duration 1 year
Labor Warranty Duration 1 year
Warranty Provider Manufacturer
http://www.sonicelectronix.com/item_21927_Kicker-CVT652-10CVT652.html