I have two 27" iMacs under this recall and I live in Brooklyn. I simply called Apple and told them it would not be possible to transport these iMacs to a store in Manhattan for servicing as I do not own a car (which I don't). They sent a service person to my house to do the drive swap. The tech was a 3rd party contractor and highly knowledgeable. We had a good discussion about the engineering in the iMacs as well as the current state of tech.

In short, I called Apple and politely walked through the issues and they did not hesitate to help me out, even after noting that I lived geographically close to many Apple stores (Grand Central, 5th Ave, etc), but also acknowledged the difficulties in actually getting to them.