I think mine turned out to be a 77.0 in. . I now know this after purchasing and ordering 7, thats right 7 god #&!* belts throughout the day and still having one on there that's slightly too big (77.5). The use-the-factory-size-for-non-a/c-5.0 idea wasnt right at all either, it said it was a 85 inch belt (way too big), so Im assuming that given size is for non a/c 5.0s with additional dummy pully in the a/c's place, not the plain delete kit. damnit.....
at least my new 160 thermostat works awesome.....My temp gauge wont even dare go up into the shaded "normal" area.