Like all Dart blocks, our Big-M block arrived machined, but it's still a good idea to get the block up into the align-hone and measured for accuracy. Mike Consolo led the way, and after learning which crankshaft and main bearings we were using, he started by measuring the mains. Using the bore gauge, he measured each main by checking the front and behind the oil hole, discovering that our mains were 2.936 inches, which is 0.001 shy of what we were looking for. We needed our mains between 2.937 and 2.938 inches. From there, Consolo set the bore gauge to hone the mains.