Can you help with fingerings for Lanz's Behind the Waterfall/Desert Rain Medley?

I'm struggling with the left hand in the Desert Rain (I think, the middle part anyway). The rest goes blazing fast, but the best I've figured out involves way too much work for the thumb and it slows down a lot and doesn't sound even. Suggestions?

Fingerings is a new one for me. How do you finger it ?