Fitting Kadee couplers to Rivarossi Cab Forward - Model Railroader Magazine

[:)]I recently purchased a Rivarossi Cab Forward, I fitted a Kadee coupler satisfactory to the tender, now I want to fit another to the front, (for Double Heading operation).
The existing front one is moulded to the cab, has anyone had experience in changing couplers over, I need some clues on the best method of removing the existing and replacing with a Kadee, which No Kadee is best, and the best way of going about and/or give a reference for me to look up a "how to site".[:)]