The importance of measuring bell housing runout.

Go look at your 60's and 70's service manuals from Dodge/Plymouth. There is a whole chapter on aligning bell housings and the importance of it. I have been doing the alignment checks on all my motors I build for over 30 years. Even Ford and GM. The only time I find something way out either face or crankshaft alignment is the aftermarket bell housing. I send them back and get one that will pass. I have a factory small block and big block bellhousings that I use to double check my finding. Also remember when you line hone a block normally you move the crank line .004" to .006" up in the engine and that will put it out of spec. The factory offset (aftermarket) dowel's come in .007, .014 and .021" settings. So if your total is .028 a .014 offset dowel will get you back to center.