Dominance of the Nucleon Decay K-channels in P_(LR) invariant SO(10)

RH rotations of the fermionic mass matrices are not observable in the standard model, but dictate the details of the proton decay in GUTs. $P_{LR}$ symmetry in the two light families leads to a full RH mixing. We give two versions of suitable broken $P_{LR}$ invariant SO(10) which leads to nucleon decay modes similar to those of SUSY-GUTs with rates in the range of observability of superKamiokande and ICARUS.