Since this is what I have, here's 2 '77-78 bumper jacks, should be the same for a '76.
Both are the same, both are 31" over the mast. The stamped text about oiling is different.
Earlier models appear to have a stamped date code on the rivet of the jack body, these do not. Early versions also have a stamped date code on the base plate, this one simply has U.
The date code is stamped into the mast on each, different locations, appears to be 14th June '77 and 29th December '77. The earlier one also has Patent 3163925 stamped.
20230504_155511 by
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20230504_155537 by
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20230504_155300 by
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20230504_155315 by
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20230504_155341 by
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20230504_155322 by
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20230504_155417 by
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20230504_155602 by
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20230504_155634 by
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20230504_155716 by
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20230504_155730 by
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20230504_160054 by
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And the reason they are only 31", need to fit under the parcel tray inside brackets and curved body.
Parcel shelf cut with jack 2 by
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