Do you have your old leaders off the rollers?
Are your present leaders "glued" to the rollers? I remember that was challenging to remove all that old glue when I redid my Ultimate II leaders. My husband used some type of scraper to remove the glue residue and then we wiped them down with some type of cleaner---sorry I don't have the name of cleaner.
I just this past week installed Zippers on my Prodigy leaders and one of the leaders on the take up roller was not straight I discovered when I zipped the take up leader to the front zippered leaders. So, I ripped that one off, and re taped it.
I have taped leaders onto rollers (Super Quilter, Hinterberg, Ultimate II and now the Prodigy) using Scotch Clear Duct Tape. Scotch makes the very best adhesive tapes. Once you use their tapes compared to others ---well, lets just say there is a big difference in how well they adhere, and how long their tapes stay put.
You need to find some form of seam line on your rollers, use the previous line or create one with a chalk line.
If you have no one to help you, this is the method I have used in the past to attach cloth leaders to conduit or metal rollers.
Buy several rolls of regular "double sided" (sticky on both sides) Scotch brand tape. It is about 3/4" inches wide. Apply this double sided tape to your metal conduit roller FIRST with one edge right on your reference line. Now, press the edge of your cloth leader to this sticky double sided tape. It will hold the leader in place just long enough for you to apply the Scotch 2" Clear Duct tape onto the leader fabric. Overlap half of the duct tape onto the leader cloth edge, and the other half onto the metal. The double sided sticky tape is left under the edge of the leader fabric. You may also do another length of the Scotch Clear Duct tape just overlapping the first if you wish, but one length seems to be strong enough.
Hope this helps---
PS. I found Karen's instructions for leaders and zippers a bit confusing. But, it could be me----I used The Quilt Connections marked zippers set, and their instructions were great for installing the zippers. I can post pictures of the zippered leaders if you want.
I don't know why it has taken me years of pinning to finally decide to try zippers. Loving them!