hey buddy, you just need to locate the hidden file "vendor.xml" and delete it. this will remove the carrier's information branded to the software.
the version os v.4.2.0.88 is the best one i have used so far. i hear there is a newer version os v.4.2.1.xx coming out on the horizon soon. can't wait to see if it improves reception on my tmo pearl.
good luck