Larry
Have you ever been up to Little Lakes Valley above Rock Creek Lake? We were there a few weeks ago (5/14-5/17) and it was beautiful. I don't know if the road is open all the way to Mosqiuto Flat t/h yet, but you can park at the upper pack station and hike in, it will add about 1.5 mi to the route.
It's not the 23 miles that you get with the High Trail / River Trail loop, but it is easy access and not alot of elev gain (10k - 10.8k if you stay in the valley). The lakes were still frozen but I would imagine there's been quite a bit of thaw with the current temps.
Here's my Picasa link: Little Lakes Valley Snow Camp
click here for pics Happy hiking!
Stacy