Auto Meter Cluster Not Compatible with Swingers?

That panel won't fit the 67-71 Dart (of any flavor) dash frame. In 72 they started using the dash frame style developed for Dusters
that panel will fit in the dash frame for 72 and up Swingers. Look for where the headlight and wiper switch is: if in the metal dash below the bezel its the older style, if those switches are IN the bezel then it's the newer style. That cluster should work fine in the OP's 73 dash

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