Running them off the passive x-over?
Sensitivity of 90 dB?
I'd go at least 250w to each door, myself. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif
Just a word to the wise. Consider using screws less then the thickness of the top mounting baffle. If it's 3/4" MDF, then use 3/4" screws. Reason being with a high output driver like that, you might want to limit the amount of energy that would otherwise be transmitted through a long screw back to the door panel. Unless you've decoupled the entire baffle from the door steel, then I think you'd be ok.
You might also consider soaking that MDF in fiberglass resin or using some Rustolium or bedliner spray on them to keep them from breaking down.