[GeorgeRud]

I think they all will work, but somewhat depends on your exhaust system. The straight pull system ( catches the trunion at the end of the arm) will fit with old style heat exchangers or headers. The angled arm will fit with the later styled heat exchangers ( I think they started with the 1975 911s), and uses a different clutch cable that bends around the end of the arm and attaches/adjusts at the middle stub along the arm.