We are talking about differences in name spelling, right? A driver's license could work. You gotta have a photo ID, however also bring along your non-photo ID with the spelling that matches your I-485 application. And make sure you specify all other names used in "all other names used" in all your applications.
In my case, spelling on passport was different from spelling on driver's license which was different from spelling on I-94. After they saw the first two, they asked to see I-94 as well.
