horsehead said The 67 block is a 430 casting with a date code of 10*11*66.Pad says C 440 12-30.The 68 block is also a 430 casting and has the date of 4*1*68. Pad says D 440 6-7.There is also an upside down A? under the 440 on the pad.Anyone know what this means? Click to expand...