I'm working on restoring a 68 z28 302 and over the weekend picked up a numbers correct block and crank in a trade with a friend. The engine had been drag raced the block is in good shape but he told me the crank had been lightened for aluminum rods there are drill holes in all of the counterweights. Can anyone with machine shop expreience tell me if this can be balanced to work with stock rods and pistons and still be reliable? Original large journal cranks can go for $1000 or more so i would like to save this one if possible.