Slick top for sure. I sold a na slick top many years ago to a local girl and she flipped it 4 times taking out a phone pole with the z, she walked out with several ribs broken and i think the leg was broken but what saved her was the slick top. I bought the car back from the towing yard and the motor was the only thing we were able to salvage and install into another z. .........dont forget to thank Jesus Christ for saving you as He has kept Me safe twice when i totaled both of my z's.