it has been a few years since i've been up to thompson but i remember a saddle going west from thompson that i was thinking to use to drop into the basin to the west.
http://maps.google.com/maps/ms?msa=0&ie=UTF8&t=p&msid=113585860418578866491.00044cbc8bd393892d897&ll=44.171124,-115.031662&spn=0.130021,0.319977&z=12