sorry to hear that...
they should be good for about 70Hz "bass" extension, with about 40watts power handeling.
they dont suit free air application at all.
they would be reasonable in about 15 litres each (0.53cuft) tuned to 40Hz...
see if you can build an enclosure under the rear deck, for both woofers, with a port in the middle //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif