So mark that line and just trim that back to the main body of the rail? I was wondering about that. The pockets that were on the table were "trimmed" with what I can only assume was a rather dull butter knife, so I wasn't sure if I should trim them more to fit or if I should cut out relief. Thanks again Glen!If you lay a featherstrip in the track, across your extension, trace a line behind the featherstrip across your extension. That line represents where the extension should be ending in the throat of the pocket, otherwise you're going to have a hard time tucking your pocket liner in place behind your extensions, which is why you always see the pocket liners curved away from the pockets.