Birth of a 1970 Dart Convertible
Add me to the list of those whom are mystified as to why you're using the hardtop and converting it to drop top status .
The factory convertibles were based on the "21" body style (e.g. , 2 door sedan ; fixed 'B' pillar) , which has a different roof line and 'C' pillars than its hardtop (body style "23") relative .