I would set the tone by running a few radio ads and billboards with Rose/Pope and Worthen/Holland being chummy. Hold a big party in the fieldhouse before the game and invite both schools. Have good food and cool games and contests, then have all the students of both schools walk from the field house to the Marriot Center together...call it the blue/green mile or something cheesy like that.
There are 65,000+ college age kids attending UVU and BYU, and hundreds of thousands of fans of both schools in this valley. One could probably turn an annual blue/green game into a profitable event for both schools and for local sponsors.