Help and info needed on different door glass set ups from 73 to 76 for a duster

I have a 76 duster and I bought the power window kit from electric life for 73-76 duster and dart. When installing I noticed my original regulator and window slide was completely different than in the instructions. After searching the Internet I found a few vague pictures that confirmed that they must have change from 73 to 76. I know to make this work I now need the glass channel and rails from a 73 but will my original glass still be usable? And what other year models have the same parts as a 73? Thanks