Just session it a few times - you'll get it.
I used to clean it all the time, then hadn't for a long time, and it was p!ss!ing me off, so that's what I did (last year), and got it after the 3rd time (both directions).
Haven't been there since early spring though, and haven't gotten it on the SS.
EDIT - Oops - just re-read your post and I'm not sure if I know what you mean.
You mean clean (from the parking lot) the whole trail all the up to the Longhorn turnoff?
Or do you mean clean the 1st rock garden right after the 2nd gate?
I used to clean it all the time, then hadn't for a long time, and it was p!ss!ing me off, so that's what I did (last year), and got it after the 3rd time (both directions).
Haven't been there since early spring though, and haven't gotten it on the SS.
EDIT - Oops - just re-read your post and I'm not sure if I know what you mean.
You mean clean (from the parking lot) the whole trail all the up to the Longhorn turnoff?
Or do you mean clean the 1st rock garden right after the 2nd gate?