Cyclobenzaprine (Flexeril) is really not much in terms of recreational affinity. It's replacing a lot of people's Carisoprodol (Soma) prescriptions, that I know and one can only be lead to believe that this is due to some people's inclination to get a "high" from it. Carisoprodol has an obvious potential for recreational use, itself being a prodrug (I think) for the delivery of Meprobamate (Miltown) an old school sedative that was so popular it caused an epidemic of addiction/dependence in its heyday.
I feel the best you will get is a slight, if any, synergy with the benzodiazepine you're taking but the clonazepam is going to be the "driving force" of your buzz, with the cyclobenzaprine remaining somewhere in the periphery. This is just my opinion based upon my personal use and seeing that I've never received "euphoria" from any benzodiazepine, save for IV midazolam (Versed), I wouldn't even really enjoy both drugs together unless I was on a stimulant comedown or extremely stressed.