You're correct about the top "square" clip, it has a dogleg bend at each end that fits over the rubber and it's reversed from the other three.
You will probably have to trim a little to get the seals to fit precisely, but be careful not to cut too much. Remember that only the thinnest part of the rubber goes over the inside edge of the trim ring, so if you cut the bulb side to length you'll end up with a small gap when the assembly is pressed into place.
[img]
http://www.octanecreative.com/ducttape/new_intro/tapestrip1.jpg[/img] Whatever works for you.
