I just picked up my Scorpion today and went immediately to work to modify my new toy. I don't know what that stuff is they used on the screw. It's a Bluish / Greenish resin which doesn't resemble any kind of loctite or Permatex product I've ever seen. I made sure I had a solid purchase with my allen wrench, took a set of pliers, and torqued it off. That resin gave a cracking sound and gave way with little to no damage to the screw. After inspecting the receiver and the screw, they really drench the screw and receiver with that stuff and it's hard! I tried to use a dental pick to pull some of that stuff off but it's really on there good. The consistency is almost like hard candy.
You could try to knock out that evil goop they used with a dental pick. I don't think needle nose pliers would work well at all. Take your time, be patient, and good luck!