Not really a bummer, the space exists to do a substantially more powerful, more efficient system in the same space utilizing aftermarket components.Wow, I didn't know that. Bummer.
As Brad suggested, the GP Factor brackets and RedArc BCDC Alpha and RedArc 150Ah battery are as close to a "drop in" as you can get, and will suffice for many people's needs (not to mention gives you ~3x the usable battery capacity)