Future canyon-carving plans and the bang-shift coolness factor sold us on keeping the original Muncie M20 four-speed in service. Off came the flexplate, in went a roller-pilot bearing (Year One PN 47392N), and on went a McLeod 30-pound steel flywheel. Itll fit either the 2.49-inch or 2.75-inch crank register diameter by using a trick press-fit insert. Our cranks 2.75-inch register didnt need it, so it was carefully tapped out with a brass punch. Because this motor is externally balanced, the crank is drilled with an asymmetric bolt pattern so the flywheel only goes on one way. ARP bolts were coated with their assembly lube and torqued to 90 lb-ft.