I may be wrong but I thought they are all the same from 85-93, all I know is every 5.0 I have seen opened up and late 5.8,s show very little cylinder wear my 94 5.8 block came from a van with over 200k on the clock and I could have just honed it. I'm thinking late 80's mid 90's blocks must have a higher nickel content or something even chevy's in those years have almost no cylinder wear BUT maybe its because most of those cars came equipped with OD trannies?