My recently published paper addressed this issue using Bayesian framework. In this paper we selected best possible GCM(s), however, it is recommended to choose RCM(s) as well. Please see my paper on link below:
Article Evaluation of CMIP5 Models and Ensemble Climate Projections ...
You can draw the PDF annually and seasonally between RCM and observed in long historica l period then biased corrected for the best to apply in future projections befor using in hydrological models
here are so many ways to shortlist the climate models for regional analysis. However, considering mountain regions and sparsely located observational network, any model selection process that could avoid using model simulated precipitation should be preferred. You may want to look into the following paper that would briefly provide an overview of model shortlisting techniques in practice and could help you in someway.
Article Precipitation projections over the Indus River Basin of Paki...