We examine pair mass dependence near threshold as a means to measure the spin
of the top quark in hadron collisions, and we discuss the possibility that a
top squark signal could be hidden among the top events.Comment: 9 pages, RevTeX, 3 figures. Contribution to the Thinkshop on
Top-Quark Physics for the Tevatron Run II, Fermilab, October 16 - 18, 199