8 lugs and unknown year could be as slow as 7.17 ratio, as that's as slow as you can stuff in a Dana 70.
To find out the ratio you can jack up one or both rear wheels and start turning the wheel(s) and counting both those turns and the driveshaft turns, then a little math and you have the ratio. That's the fool proof way of finding out what ratio you have. Do a search on how to find rear axle ratio on this site, as I know I and others have described the procedure a few times now.
Grigg
