Need Help w/ Intake Details for '67 920 Heads on '66 273

It sounds like that extra 1/16" is the difference between how I measured it (caliper inside hole) and measuring the bolt from thread to thread on the outside.

According to this table, http://www.mopar1.us/Aengine.html , the 920 heads, both adjustable and non-adjustable, were only available in '67. I have a line on an Edelbrock 4bbl intake but I want to make sure it'll bolt up and I can get a proper gasket for it (I want to do it right the first time). I'll know the Edelbrock part number later.

Thanks for the help. Now it's on to the search for headers (Sanderson says they have one, but I don't know if it'll work w/ power steering and whether I need a smaller starter).