I looked over the satelite views and couldn't find any sign of a trail. The rock slope is very easy to find. 

My sources are pretty simple. On a PC, the best aerial imagery up the Clackamas is on Bing. Under the 'birds eye' tab, click on aerial. You can use Birds eye to find terrain profile, then go back to aerial for a very clear view. 

The best I've found is using Apple Maps on hybrid. Using an iPhone 4, 4s, or 5, turn the brightness all the way up and then go to hybrid on the maps. Click it on 3D and map surf away. The apple maps used like I mention is how I've been finding some good waterfalls lately.

I went to the Bing maps and looked around a bit - although the images are a bit better than the google ones, they still have long shadows and so there is a lot of detail that is hidden in those shadows.  I did not see anything that looked like old tread either, but the images are still rather indistinct.  I wish my brother still lived out here - he could fly me over the area for a closer look....I guess it will require an on site reconnaissance next summer.  It would just be nice to have a smaller area to search.