I opened up the channel a little larger than factory. I took a bolt with a head on it that was a little larger than the channel. Then take a hammer and pound on the bolts stem with the head in the slot. The head of the bolt will force the channel to widen. Slip your windlace in and then go back and crimp a few places to make sure the windlace doesn't pop out. Take a look at my site with the '51. You can't tell that I widened the track. The other way was way to much for me. Cecil...........