[BRENT in 10-uh-C]

Yes, with 3 people, mark both brake drums and the drive shaft with a piece of crayon/chalk/tape. Have a person on each brake drum slowly rotate the drums simultaneously keeping their marks at relatively the same location in the rotation as it is being turned. While this is happening, have someone count the revolutions the driveshaft makes as the 'Brake Drum Turners' make one complete revolution. If the driveshaft turns roughly 3¾ times, then you know you have a 3.78 ratio. If it turns 4 times, then a 4.11, --and 3½ turns of the driveshaft make it a 3.54 ratio.

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