Charlie, don't think the maxi rail has any affect on the trigger block, but remove it anyhow as I would suggest using some heat on the steel tube to try and loosed the trigger block thread. I repair at least one airsporter a week and often have the same problem. The maxi rail is in a set of locking slots and needs to be tapped backwards before it will lift out. Using a heat gun apply heat to the steel tube and spray some WD40 in and around the thread and eventually they do break free.I personally use a blow torch but I am very careful not to let the metal discolour. Never had one that is impossible to move. You will have to leave the barrel and cocking link in place to stop the tube turning in the vice, be sure to protect the metal surface from jaw damage.
Baz
Last edited by Benelli B76; 06-02-2017 at 06:56 AM.
BE AN INDEPENDENT THINKER, DON'T FOLLOW THE CROWD