@edcyn: Yeah, The Mountain LP is getting hard to find. The album was released on both CD and LP in 1999 on E-Squared Records (the label started by Earle and music businessman Jack Emerson)---I have both, and reissued on CD and LP in 2017 on Warner Brothers Records.
Music Millennium shows a copy of the WB CD in stock, but their website data and in-store stock often differ. I’ll give them a call after they open today (Sunday), and have them check the bin. I’ll let you know, and if you’re in luck you can order it online.
The show was definitely at The House Of Blues on Sunset, I remember it very well. Steve and all the Del McCoury Band members stood in a semi-circle around the single mic; when Steve was singing the verses he would move in closer to the mic; when the band sang harmonies (they are excellent harmonizers) he would move back in line with them. When an instrumentalist took a solo that player would move closer to the mic, returning to the line at it’s conclusion. Bluegrass players start young; by the time they are 12 years old they are playing at professional level. Marty Stuart joined Lester Flatt’s band when he was 14 tears old! That’s about the age when a lot of Rockers pick up a guitar for the first time, and aren't fully developed players for another ten years after that, if ever.