When using a managed library, naming files is pretty much irrelevant. Instead of renaming files, you should be able to correct this consistent metadata.
As long as the files are named with the same Album, and the track/disc numbers are laid out accordingly, the files will be played in order.
Consider the following:
As you can see, I have one album in perfect track order, and a recently added Audiobook in total disarray.
Screw renaming files! iTunes does that for you anyway. Mass-edit all the consistent tags first.
Grouping them by total number of tracks, disc, album, and artist, will organize them all into their own section initially. After doing so it's a simple matter of clicking on a single track, entering it's specific track number, and clicking next.
The coolest part of this process it that iTunes will maintain focus in the metadata field you select, so once you have everything else out of the way, simply leave the mouse cursor on the 'Next' button, type a track number which you should be able to get from the track name, then tap on the mouse button without moving it.
Two minutes later, you have consistent metadata: