I have a Series II and want to add a three point seat belt system. Looking for information on proper, safe mounting locations. Currently I just have lap belts. Not even sure if the mounting locations are correct. I've found different holes in the floor pan that indicates they were moved around. Would also like to know where to mount the shoulder harness. Is it necessary to install some type of mounting bar behind the seats to get the mounting point above the shoulder? Thought about installing a roll bar, but that interferes with the convertible top. Suggestions? Thanks!