58 master cylinder problems

[59 camaro]

hello, im new to this site, this is my 2nd truck ive started but my last one was almost 10 years ago so im kinda rusty on it.... i need to remove the master cylinder and its been like 3 days ive been messing with it, ive soaked it with wd40 and other lubes, ive tried to remove the brake pedal arm off the master cylinder arm and nothing, is the pedal supposed to be bangged out with a hammer or does it screw off? ive removed the nut but the damn pedal wont come off and i have no room to remove the pin that holds the master cylinder into the arm someone please HELP!!