This is all really simple. Go online and get a parts diagram for the undercarriage. Take pics of the car on a lift (a helpful mechanic can do this--take 10 min). Compare and contrast.
Here's an example of mine:
REVO luggage $100
More info
2007 Honda Fit $4,400
More info
Promote your business here - Businesses get highlighted throughout the site and you can add a deal.
Has Planet Honda given you the impression that if you can just come up with an official name for this thing they are going to replace it for you? I'm having trouble envisioning that scenario given what I've heard about Planet Honda.