Last night I attempted to install my new CTR stock on my Stag lower. I checked to make sure (website and measuring) that I order the correct milspec CTR stock for my Stag milspec buffer tube. Well, I was so excited to install the CTR stock that I did not read the instructions about pulling down the metal posts on each side of the locking pin in order to install the CTR stock. I got the stock about 1/4 of the way on the buffer tube and now it's stuck. I have since tried to pull down themetal posts on each side of the locking pin, and I'm able to do so, but the stock is not budging. Could you guys provide me with some assistance? Thanks.