Ok, I'm under Nyquil Influence and I am directionally challenged but maybe I can help?

You know where the Sammamish trail goes to Marymoor? When you go over the bridge where you'd go into Marymoor, go out to the street instead of curving 'round over the bridge. Take a right when you get to the street but ride on the sidewalk. The major intersection is maybe 1/2 block to your right, cross it and the trail goes right alongside the 520. Make sense? I can ride it with you if you'd like but it's fairly straightforward. Be forewarned, the initial hill you will face isn't like the rest of it. It's a short bit of nastiness and while that portion of the trail is mostly uphill until it ends (goes about 4.5 miles or so), the first part is the worst.