If that's Don Welch's 427 targa, it was the first one ever built, done 5 or so years before any such 'kits' were available, before Hall did a few similar cars and well before Pavesi did some targa-topped GT5-S cars for the DeTomaso factory. After the FE engine was in place, Don punched the throttle during his first test drive and the body flexed enough from torque that both doors popped open. Much time and engineering went into stiffening the monococque so that didn't happen again, even when it was open-tracked a few times. There's quite a bit of history on that particular So-Cal machine.
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