B5 int/B7 ext was this possible in '70 Duster

Hi,
I'm working on a '70 Duster. It has a factory B7 interior and exterior. I am thinking about changing the interior to B5 but I'm not totally convinced yet, just thinking about it. The car has the base interior with bench seat which will be replaced by bucket seats. Was a B5 interior and B7 exterior a possible combination in 1970? I like the blue on blue, thats not changing. Think I'm just nostalgic for the B5 interior in my first Duster that was Painted Spinnaker white...that was a nice combination. Any comments, welcomed! thanks, nick