I can’t find any info on how to bench test this motor. Which wires get hooked to what to test? I’m assuming the jumper box negative clamp goes to the case but don’t know where positive goes.

 

The motor case gets grounded. The single (formerly) red wire is the armature feed. The yellow and green are the stator windings, one for each direction.
Ground the case, apply 12V to the red wire and to one of the two stator windings. The motor should turn one way. Swap to the other stator winding and it should turn the other way. Green should be forward or down, yellow should be back or up.