A momentary push button switch 73 is placed in {HEAD ~ axial alignment} with {TAIL ~ the drivetrain assembly} 71 
A momentary push button switch 73 is placed in { HEAD ~ axial alignment } with { TAIL ~ the drivetrain assembly } 71
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH