Another story-based achievement that can't be missed. Simply use a caricature of George McFly (obtained by using the photo on Zane the bartender) on the empty frame behind Officer Parker. Then speak to Trixie to convince her that Artie was added to Kid's "wall of fame", which turns her against Kid Tannen.
Make sure you don't place a photo of Marty in the frame! There is a game-breaking bug that prevents further process, so make sure you only place the George caricature in the frame.
(Thanks to OllyBongo89 for the extra info)
See the section on Chapter II in my Walkthrough here on TA for a more detailed guide on this part of the game.