I can tell you first hand not too get Heddman. I've been fighting with a set for my 72 Nova for a long time. Not even close to fitting and the spark plug access is horrible. Had to make special sockets for the plugs. In the places where they hit I had to cut them out and weld pieces in. I worked on them for hours very fustrating.
Should have got a set of Lemons. Good Luck