I am very proud of myself for this achievement. I've always done 70 star or 120 star to avoid a BLJ, due to the fact that I'm not very good at it. So for completing a 50 star run and achieving the Endless Stairs BLJ, I am just super proud of me.
Unfortunately, I didn't record the actual run itself, just the finish. I had to do lots of BLJ practice on Bob-omb Battlefield and Wet-Dry World, and I even got so frustrated with the practice that I took a break and just did a Tick-Tock Clock star (which is the reason I have 51 stars instead of 50).
I know a lot of people can do BLJs easily and probably aren't exactly proud of this finish, but that's fine by me.
-sm64mk