I put a 9 inch from a 71 F-100 6 cyl. 60.5 inches wide. most 6 cyls had low ratios, mine came with a 3.70. width is perfect.
link to my build
http://67-72chevytrucks.com/vboard/showthread.php?t=296770


1950 custom streetrod build
http://67-72chevytrucks.com/vboard/showthread.php?t=296770

71 corvette conv, 525 hp big block