Shortwood started the evening protecting a run of five games without defeat, but fell behind after 38 minutes to a goal from George King.
And just 2 minutes later, Joe Tumelty doubled the Larks lead.
But the home side went into the break 3-0 up when Cory Simpson grabbed the third.
The second half was all about game management for the home side, which they did successfully to move up to twelfth in the table.
By Steve Whitney
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