  We discuss the effects of mixing of scalars belonging to left-- and
right--chiral MSSM super--multiplets on the process ${g}{g}\rightarrow \hnl
\rightarrow \ga\ga$, which is a promising channel for the discovery of the
lightest CP--even MSSM Higgs boson at the LHC and the SSC. The effects of the
left--right scalar mixing are small in most of parameter space. However, there
exist regions where the mixing is important. Due to mixing, there can be large
enhancements of the cross section in a region of parameter space where the
no--mixing approximation yields a value that is too low for experimental
discovery of the $\hnl$ at the LHC and the SSC.
