I have recently acquired a 1967 WRB 350 stored poorly in a barn, am working through the bike and have a glitch, I cannot get the chrome tube off of the top of the lower fork. I need to do this to get to the nut that holds the seals in. Does not appear to be threaded, tried gentle heat. Need advice before I do something foolish and mess up the chrome tube. I see no way to grip it inside or out without possibly causing damage.