John: My Panorama Loop started at the bottom of the 4-Mile. Certainly easier to do at the start of the day, with a rewarding snack or early lunch at the GP store. The other issue is the bus situation... Ride the bus from Happy Isles, switch buses at stop #2 (cross the street to stop #4), ride to stop #7. I think I would prefer starting from the valley floor. It would be a bit longer drive for you, though. It is a great hike -- I definitely recommend it. Here's a link to my writeup:
Four Mile Trail -- Panorama Loop Hike 
