Need a few suggestions about possibly modifying an existing cabinet. First off, it has been a while since I have played bass, but I still managed to hang on to some equipment in the event I decided pick it up again. I have the original GK 400RB, Peavey TNT150, and a Randall Road Warrior 215. The GK head is obviously underpowered for the 215 cab, but I was wondering if it would be worth it to modify the cabinet to better match the400RB? The cabinet measures 34" high X 24" wide X 14" deep(OD), sealed. It is loaded with two Jaguar speakers, , one of which seems to be going bad anyway. Would it be worth it to maybe cut a new front baffle and customize the speaker configuration and perhaps utilize the known good 15"? It's nice having that bottom end but I would like to have a just a bit of punchyness that the 10" drivers deliver. Also, another goal would be to also get it to 4 ohms to match the head. Seems like a waste to let a perfectly decent cabinet go to waste seeing as decent drivers aren't all that expensive. Of course, I know squat when it comes to tuning or building a cabinet. Or....should I just run a 2 x 10 extension on the TNT and be done with it? It has been several years since I played either rig, but both seemed just slightly underpowered, but then again I don't think I drove either amp to it's full potential. Or maybe I should run both amps in tandem? Not wanting to put major dollars into this, but trying to get a respectable volume and tone...still need to buy a bass after all. Any suggestions other than buying a brand new cab would be appreciated.