Root Explorer immediately asked for SU privileges, which I granted. You can browse any directory and mount/remount right from the app. As I suspected, according to Root Explorer, /system was already RW. I went right to /system/app and deleted all the crap that I never wanted that always runs in the background. Amazon MP3, Blockbuster, CityID, etc: GONE. The only app that is alluding me is the Kindle app, as I can't find it in the list anywhere. I'll also have to find a more comprehensive list in regards to what is safe or not safe to remove.
And out of curiosity, what is the purpose of changing .apk to .bak? I understand that I should have probably backed up the .apks before deleting in case I changed my mind, but I never want to see them again anyway and they are available on the Market.
This app is a godsend. Seriously.