REBUILDING 73 DUSTER DRUM BRAKES 10 x 2.5

That is the left side (drivers side). The "secondary" shoe is the one with the longer lining, it is also a different lining material in 99% of cases. The secondary shoe has all the ebrake parts and self adjusting pieces. The right side is a mirror image. Its best to do 1 side completely, then the other. That way you can use 1 side as a reference. Even the adjusters are different threads, one is Left handed. When the adjuster wheel is rotated "UP", (CW), the adjuster gets longer (it unscrews).