Not to discourage the op in anyway, and I wish the best. But here is how I look at these things when I give my opinion:
IF that block was for sale, and I (or anyone reading this) were told "yeah, it had a crack right here, but shoot, we put a plug in there and she's as good as new....." would you still buy it???? If you would honestly walk away, and look elsewhere, then that is how I give my opinion. Not trying to save a 2nd generation hemi here, not enough value in a 360 block, IMO, to not replace it. They are cheap and common. If something gives, the cost/loss will be much greater.