Just taper off the phenibut. Considering the doses used, there is way more wiggle room in gradually decreasing the dose than with something that comes in such small doses as clonazepam. And as was already mentioned, clonazepam and phenibut work at different GABA receptor sub types, so its not a suitable drug to switch over to in the first place. Clonazepam will relieve some of the anxiety and restlessness associated with any kind of GAGAergic withdrawal, but only take it if you absolutely have to have something to take the edge off. If you are going to use it at all, use the lowest doses possible and don't take it regularly. Take maybe .25-.5 mg AS NEEDED ONLY, and I wouldn't take it more than once or twice a day MAX, amnd maybe only 3-4 days a week. Seriously, it would be a shame to come off phenibut and be left with a benzo habit, which is magnitudes worse to come off of. I speak from experience. Just taper the phenibut, stay hydrated, eat healthy foods, try to exercise and get proper sleep. Take vitamins, especially B vitamins, and supplement with magnesium and maybe l-theanine.