1/4 window has slack....help

[ctrain22]

I have a 68 442 convertible with power windows and am having problem with closing the driver side 1/4 window. I catches the lower part of the 1/4 class weatherstip molding. If I pull up on it and hold it up while I close it, it will close ok. I can take the window and rock it back and forth. I replaced the rollers on the window, but there seems to be way too much slack on the verticle part of the regulator. Almost seems the rollers are too small. I did get the roller from National Parts Depot and they were for Chevelle. Are they the same as Olds rollers? Are olds rollers thicker? Is there any adjustment to take the slack out? Any advice would really be appreciated.