I've assembled the 2pi towers and glued up everything except the front. I need to put in all the R-13 before sealing them up. I have a question about where to attach the R-13 - if the R-13 is attached to the rear, how is it cut around the port? How much clearance? Or is it better to attach the R-13 to the inside of the front piece? I'm trying to attach a picture, if it goes through you'll see how far I am. I need to attach the cross braces, then I'm about ready to close them up. Thanks, Duncan McBride