Novice mechanic here trying to save $$ by replacing the gas tank in my 73 Mach I which sprung two leaks. The straps are off, and the only thing holding the tank now is the filler neck. Does anyone know how to get the neck out/apart from the old tank? I will have to reuse the old neck because I cannot find any new/reproduction necks for 73s in any of my parts books. Thanks for any and all help.