Either the mighty slant 6 ripped the transmission mounting loose and chipped the mounting flange.... or a ding dong forgot to tighten the mounting bolts and one fell out and the transmission flailed around chipping the housing... no one will ever know...... New speedo gear installed to to match the drivetrain... time for a test drive. Note that these pushbutton speedo gears are the same as standard transmissions so Brewers carries a full selection.