What an amazing hike! This was very challenging yet very rewarding once you finally get to the lake.
There is a lower parking lot which is where most folks park. Getting up to the trail head is not that daunting and I could have made it in my Forester(or any vehicle with 8 inches or more of clearance). Compared to the drive up to Grays and Torreys, the road up to there is a cake walk.
The overall trip is 12 miles as listed here but there is a sign about a mile in that says the lake is 4 miles away. The last 2 miles of this hike is where the incline sets in(and you ascend over 1k ft) while the first 4 miles are fairly flat as you go through the valley.
Overall, this hike is manageable and the lake itself is beautiful. It is covered most of the way with a few river crossings that you do not need to remove your shoes for. It would be amazing to camp at one of the spots right next to the lake and have the views looking over the valley be the first thing you see in the morning