I don't think the actual bolt sizes are different. I think they changed the head size from T40 to T45 at some point, probably cause they are that easy to strip if you are not careful.

The 108 or 100 mm flanges don't say if it's a 7" or 7.5" diff. A lot of 7.5" diffs also use 100 mm flanges. Only the 2wd cossie and Scorpio mk2 use 108 mm flanges. Although the Scorpio and 2wd cossie flanges are not interchangeable, due to the 2wd cossie being LSD and the Scorpio a normal open diff.