I inherited an Akela 177 back from my son that said he will never use it. I went to take the stock off the gun with a 5mm hex key and low and behold, the top of the hex bolt seems to be stripped. I can't get a 5mm hex key to grab at all to take the bolt out. I have googled on "howto" take a bolt out in this condition, but was not enamored with the results. Can I get a shout out from the machinists/engineers on the forum to give me some suggestions? I want to put in the Airgun Revisions Tuning kit which consists of the smaller spring to get the shots down to a consistent level over the 3.5" spring that the Akelas are shipped with. I have hand tremors so some of the more "delicate" options aren't good for me!