I just read this tip about removing it from the box part and then attracting the carb side first on another old thread. I'm kicking myself for not thinking of that. I honestly don't know how you even mount a S boot on the sudcu bell adapter without doing this. The very 1st time I tried to install the carb I had to mount the boot on the carb off the bike and let it sit awhile to stretch it out. It's a pain. Remove the bolts for the regulator and let it hang to for more room. Put the carb in the intake 1st. Then put the airboot on. Drop the subframe. Loosen the carb from the intake to reinstall the boot back to the box and tighten. Use a big screw driver to "stretch" the airboot to get the carb back into the intake fully seated. Done!