Joe, Thanks. I'm off to an old wrecking yard today to sort through hundreds of old flywheels in search of a flywheel for my 66. I had toyed with the idea of using a later flywheel and simply remachining the bolt holes to fit my 400. They are not off by very much I've found. But I am unsure of how they balanced the flywheels. The cranks, at least in my experience, area all balanced at the factory. So if I reset the holes and static balanced the wheel it should work fine. I think I'd also use a fluid filled harmonic balancer on the motor to ensure a vibration free motor. If I do find one of each I may go ahead and try the idea out. If it works it would be the salvation of many of us with the older rigs. Not to mention the savings over Joe Mondello's $400 flywheels. Not that his aren't worth it - just really spendy when you are on a fixed income and working like we did in the 60s and 70s on these automobiles. Thanks again. BTW - Mondello's tech line will FAX anyone a copy of the bolt flange differences with schematic included. Steve