I have everything bought and installed from http://www.nostalgicairparts.com/ except the evaporator. I measured the indentation (interior side of firewall) from the old heater box and it's 16w x 9h. NAP has only slightly larger ones listed on his site. They will work, but I was wondering if any other brand might make a differnet size (already tried Vintage air). It would be nice if something just tucked right in there perfect. Has anyone else installed in-dash air (as opposed to under dash air).