ok. i managed to figure this out myself so here's the info for anyone stumbling on this post via a search engine or something.
Once you have a rooted droid and the ability to use the su command:
if you have adb on your computer you can do this in a basic terminal with the device connected, otherwise i guess you'll have to do it in a terminal emulator on the device.
basically follow the instructions to remount the system partition as rw:
Mounting /system partition in read-write mode in Android - adb, android, HOWTO, mount - Black God
then the instructions to disable the search buttons are at:
disable the search button
if you want to disable other buttons or switch around assignments, just look for the corresponding signifiers such as HOME and SEARCH and the button numbers they are associated with and comment them out or switch them around as need be.
this will let you remap your droid's keys completely as far as I've been able to tell.