Is there some reason not to use the kickdown? Once the OD is engaged, it won't disengage above 30 MPH unless the kickdown switch is used. I'm not sure if turning off a manual switch would allow the solenoid lock pawl to retract, unless the clutch pedal is also depressed to unload the drivetrain. The kickdown does all that automatically, in a fraction of a second.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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