I had to cut it since it was practically melted onto the tank. Wish I didn't have to but too late now... MY FSV died and decided to change the return and supply hoses while everything was disconnected. In order to drop the tank I have to cut the neck. The same with the rear tank's neck but...
trying to find a suitable replacement for my filler neck. No luck as yet, but will try junk yards soon. 84 E250 6.9 front tank. shot in the dark but better than a dead van...