You have to defeat the glue before the nut will shift easily, and yeah; sometimes grabbing with the pliers or drifting them out with a softface hammer will work a treat. If the glue is being stubborn, though, putting a domestic iron - on a low heat - on the nut briefly will often defeat the glue and allow the nut to be removed. Generally though, there's only a couple of drops of white glue holding them in and a quick tap with the afore-mentioned hammer will do the trick!