Obviously you don't understand the drill down of the mod. Yes, it is generic, I've even had people use this same mod on Printer Catridge stores, Auto Part stores, etc.
There is no categories to choose.
Look to the right.
http://shopping.lightningmotorsports.com/customer/home.php
I realize it has quirks and could handle some polishing, however overall it does the same EXACT thing yours is doing.
There is a "Model". Most average consumers are not going to care for a "Sub-Model", or such. Just the generic info on the car/product they own to find any relative products available.