Any repair may or may on work. Why take a chance, water may start to leak while on a pass and you crash or take the person in the other lane out. I’d use a different block.
I agree it may or may not work but it wont leak much if it does with block filler past the cracks so that's not a concerne. The best block for this to make good power is the 361 truck, a sleeved 400 or an unbored 400 which I have but am saving for the Superstock 383. I can sleeve a 400 but it's a slow tedious job with my old boring bar and a sleeved block would take some time to settle to it's new state.
