I had the same problem with my 78 that has a Carrera tail. New duel lid shocks didn't help. I then discovered that there should be two small rubber nubs on the engine side of the deck lid. These rubber nubs push the deck lid away from the body when the release lever is pulled. Perhaps your's fell off or are in need or replacement. The rubber nubs will not cause the deck lid to spring up but will lift the deck lid enough so that the latch clears the mechanism, allowing you to lift the deck lid. I'll post some pic tonight if you need them.
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Paul
78SC Targa
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