I've recently replace both regs in my '77 40, along with all the other felts, guides and related door stuff. The problem is on the passenger side only- after carefully installing it, I noticed a "glitch" when rolling DOWN the glass. A hesitation, like it was hitting/interfering with something. After watching it in action, I see the REAR-MOST nylon wheel that rolls along in the channel of the regulator gets to the very end of the channel during the roll-down, hangs halfway out the end, almost allowing it to fall, then as the window continues downward, it reverses slightly going back into the channel a little. The travel limit tabs that are supposed to keep the wheel in the channel, were flattened a little, so I bent them back perpendicular to the channel as I thought they should be, and upon repeating the up & down cycle, they were bent back flat again. I've tried to shift things front to rear, and take up slack, putting a bias on the window mechanism, etc, etc., to no avail. I'm out of ideas- Anyone have an idea??? Thanks!