I refer to the sheet metal dash as "dash house".The standard and rallye dash houses are different. To cut away more of the standard dash opening so the rallye panel will fit in there has been done but, There are extra holes in the sheet metal to fit at the heater rasio bezels and the holes where the instrument panels mount are in different loactions.
So if you purchased a rallye dash house from a pre 70 you would have a ignition switch bezel in the dash to fill. The best thing I have found for that hole is a control wand to a right door remote mirror.
Avoid the 68 rallye dash. It had lower dash pads requiring mounting holes, totally different ash tray assembly, column cover and more.
Bottom line your choises are , 67, 69, 70, 71, rallye dash houses.
I shouldn't toot my own horn here but I must tell you my DeMonDIN irallye panel is the optimim choice in my opinion. Dont buy it today though. Give me until about June to successfully complete my current project. I promise it will be worth the wait.