I see the 1971-75 GM convertible top guide recommended as a good source of information. But aren't those the 'scissor top' introduced for the big cars in 1971? Is it worth buying? Is our top the 'two part' top? Or a 'one part'? This is all new to me and I am researching as much as I can. I just got the 'Convertible Top- Restoration and Installation' by Fred Mattson. I also have the 1968 FSM and Fischer Body manuals. So far it is all clear as mud.