how much hp are you making ? here are some things to think about a new line bore this will move crank.005 or more to the cam and if this has been done to your two bolt .re fitted with 4 bolts it will have to be done again .005you can get timing sets for this but with this they so much 0.10 you can use gm caps but they will have to be fitted to block they not just drop in thing s like side crush so cap will not walk drilling to two holes in the main web of block this dose not help if you go to deep you will hit oil you gm rear cap will the thrust line up ?with block if not done rigth end play can be good or not not fun to fix s i have not seen to many times on a big block where you need it . they are better places to spend money you can make 600 hp all day long with 2 bolt mains and 3/8 rods this is gm best block in stock form i built many seen them go to7000rpm with two mains 3/8 rods mud trucks 7500rpm two mains pull truck 7500+ two bolt main and i can go on they call them rats they are hard to kill !!