This is one of the slowest steps in the process. Take caution since the glass can crack or shatter if done too aggressively.

Step requires gloves.

With two spudgers or opening tools, one small and the other large, carefully and slowly place the smaller one between the rubber stopper and the glass tube. Next, slowly apply pressure with a prying action to free the rubber stopper. Repeat around the stopper to eventually detach it.

Once a small portion is lifted continue the prying step, with the larger opener.

Stop when about 60%-75% of the rubber stopper is sticking out.