well i can tell you that lift predates 1989, that was the year i first started working for yale in the carolinas.(worked for them for almost 18yrs)
You could try calling the yale dealership and they could fix you up as far as ordering parts? maybe even get you a manual from the factory...
BUT this is a huge MAYBE...
This lift is older than methuzal so i wouldnt bank on it ;o)
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