Another idea could be 'Shot of the Month', be it a mod, dyno run, moving shot, interior shot, or exterior. That may allow for more submissions, as well as add to the creativity. That might make for some pretty 2GNT related photos, as well as not putting a limitation on what pics can be submitted. That can also allow people to take pics of their cars being worked on in a garage, as long as the pics themselves are worthy to be posted. This could also spark other members to tinker on their 2GNTs more.
Just looking at it as a way that will let folks showcase their passion for 2GNTs in much broader way.