Bridge Bay within the park is definitely a good option and roomy for any level of experience in parking an RV! As for West Yellowstone as a suggestion, yes, there are many options there with Grizzly RV and an KOA there. We prefer Bakers Hole CG, 2 miles North, with electricity and plenty of room. Baker's Hole is first come, first served and that's the only drawback. So, you have your homework planned for you. At the recommendation of another person and forum here, next time we go to Yellowstone, we're staying at Buffalo Bill State Park in a hookup site so we can check out that side of the valley.