Corollary 7

Let T and $T'$ be two maximal tori of G, A a subset of T and $s$ an automorphism of G that takes A into $T'$. There exists $g\in G$ such that $s\circ$ (Int $g$) takes T to $T'$ and coincides with $s$ on A.

Let C be the centralizer of A. Then T and $s^{-1}(T')$ are two maximal tori of $C_0$; every element $g$ of $C_0$ such that (Int $g$)$(T) =s^{-1}(T')$ has the desired properties.