Eary-Late

I have heard some say that early and later blocks are different in relation to engine mount pads and bellhousing/starter motor mounting. Then I have heard others say the differences didn't come in until the 462.

This is something I have not nailed down but would hate to say they are the same.

If the guy can get you a 462 crank, why not have him true the cylinder bores and bore them to take the stock 462 pistons. This would keep you from buying expensive race pistons which you don't actually need.

The machinist should have the ENGINE SPECIFICATION SHEET and will be able to determine if there is any diference in balance (flexplate-balancer) between the two. You may have to pay extra to have it balanced.