These are some models inspired by the feature model of the
40-Model set #8540. This model also appears in the manual
of the 50-Model set #9550. In each case, the model's
front legs are the ones driven by the 1.5" 3-flat Pulleys,
as in the original Mammoth.
Click on the images to view an enlargement.
First variation, with rolling back feet.
Second variation, with dragging back feet and shorter legs.
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The instructions for the Mammoth from the manual of the 50-Model set.