It worked, just like Don said it would. I didn't register it in 2012, just went up there with my title yesterday and asked to register the car. All they cared about was that its 2013 and the car's an '88. My birthday being only 3 weeks ago didn't matter.
For anyone who wants to register a '88 and didn't do it in 2012, you can probably do the same thing. You won't need to get it passed 1 last time.