  We examine the phenomenological implications of light $\tilde{t}_R$ and
higgsinos in the Minimal Supersymmetric Standard Model, assuming $\tan^2 \beta
< m_t / m_b$ and heavy $\tilde{t}_L$ and gauginos. In this simplified setting,
we study the contributions to $\Delta m_{B_d}$, $\epsilon_K$, $BR(b \rightarrow
s \gamma)$, $R_b \equiv \Gamma (Z \rightarrow b \overline{b}) / \Gamma ( Z \to
  {\rm hadrons})$, $BR(t \to b W)$, and their interplay.
