I started this here because I know a lot aren't paying much attention to garage thread now. I got doors from Wayne Dalton. I can follow most instructions but these are tuff. The one thing I can't find is what size opening do I need to start my framing. Jambs and header I can handle but what size do I set them?? Jambs go flush with edge of block but how wide?? 8 ft doors but different type doors require different size openings to accommodate the hardware. I need width of opening in block and height to hang header. Can anybody prove how dumb I am?? www.dasma.com tech data sheet # 161 Connecting Garage Door Jambs to Building Framing.