The gluino contributions to the $C_{7,8}$ Wilson coefficients for $b->s gamma$ are calculated within the unconstrained MSSM. New stringent bounds on the $delta^{RL}_{23}$ and $delta^{RR}_{23}$ mass insertion parameters are obtained in the limit in which the SM and SUSY contributions to $C_{7,8}$ approximately cancel. Such a cancellation can plausibly appear within several classes of SUSY breaking models in which the trilinear couplings exhibit a factorized structure proportional to the Yukawa matrices. Assuming this cancellation takes place, we perform an analysis of the $b->s gamma$ decay. We show that in a supersymmetric world such an alternative is reasonable and it is possible to saturate the $b->s gamma$ branching ratio and produce a CP asymmetry of up to 20%, from only the gluino contribution to $C_{7,8}$ coefficients. Using photon polarization a LR asymmetry can be defined that in principle allows for the $C_{7,8}$ and $C_{7,8}$ contributions to the $b->s gamma$ decay to be disentangled. In this scenario no constraints on the ``sign of $mu$ can be derived.
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