Glad you liked that video, thank you @krazypoet! I live about 20 minutes from that spot so I'm often out getting photos in the area. If you're ever in Truckee, please feel free to let me know and hopefully we can meet up and hike that tunnel. Here's a google map with the parking area pinged.
https://goo.gl/maps/j38UMhamSZ62
Cheers!