Scott, your advice is appreciated. Here is what I know: The serial number of the car (137053-1) puts it in 1923 10-B. The engine number (E85851) is in the right range for 1923. The disc that was in the car is rigid type. I cannot be sure that the clutch was not changed at some time in the past. The Franklin parts book lists 2 flywheels (see page 716- 26051 is for B&B rigid disc and M&E clutches, 30502 is for the B&B flexible disc clutch. There is a note with 30502, "Flywheel to crankshaft cap screw holes countersunk." The flywheel in my car does not have countersunk holes. On page 717 of the parts book, there is a list of parts needed to convert from the rigid disc to the flexible disc. The list includes the clutch disc, flywheel to crank cap screws, nuts, and crankshaft rear oil retainer. It also says the holes in the flywheel must be countersunk using a special tool. The conversion seems like a big job! Maybe I should be hunting for a M&E complete clutch. The transmission did not make any unusual noise until recently when it became very noisy, due to a bad bearing. Shifting was erratic, but the clutch brake was in pretty bad shape. Tom Rasmussen is currently rebuilding the transmission.