Convert spot C to PC (color bridge)

I receive files with spot PMS colours using the old coated library (eg 491 C). I convert to CMYK as the jobs are being run CMYK. Unfortunately the conversion is very poor in comparison to the Color Bridge conversion had the colours been labeled 491 PC.

Is there an easy way to run an action list on a file converting spots to their Color Bridge equivalent name so the final conversion to CMYK will be better?

thanks
Barry