I started poking through the stuff I got when I purchased the car the other day and as I was walking by the engine I noticed that the pistons (heads are off) said 060 on them... I haven't gotten out a dial indicator or anything to measure, but it seems that if it is 60 over, that might be the upper limit... I have heard of some motors going to .080, but I am not sure.
Also, I have no idea the shape of the motor as I just got it and stuck it on the engine stand to get it out of the back of the truck. It looks to be date coded correctly, but I haven't checked the numbers to see if it was matching. I don't believe it is. I haven't pulled the pistons to see if the walls were scored or not, but I will do that when I get some time to see if it is just a boat anchor or worth rebuilding.
Thanks,
cb