Sorry if I'm being Captain Obvious here, but,
Make sure you temporarily space the lower rail from your frame seam with something solid during placement. Its a PITA if the slider hits your frame over bumps when it's too close. Mine is a tad too close on one side, so during winter, ice gets wedged in there and makes some noise. I can think of a few rocks that could have pushed them up a few mils... Anyways, like you have to worry about snow.!

Good luck!