Hi mclsound,
The narrow cabinets won't be a problem as the drivers are only playing bass.
I believe your cabinets are too large. The drivers have a fairly high Fs and don't require such a huge cabinet. For optimal results use a 100 Litre internal volume for both drivers. You'll also get a better transient response as well as improved power handling in the 40-50Hz range.
Best of luck,
Chloro
Regards,
Chloro