The tape is a foil tape used for taping seams and is somewhat sticky, but not like a duct or packing tape. The dampening material I used has an adhesive on one side, and is pretty sticky as well, but it had seams being a 12" wide roll.

As for the crossover placement... not too sure. I was thinking about this, too, as I was going to use the Orion crossovers I bought, but I never did. I was thinking of mounting them under the passenger seat, or just finding a place in the doors to zip-tie them to.