Help! 73 sport seat rebuild!!!!!

So I’m currently in process of starting to redo the rear seats. I can’t find a video anywhere that shows the kind of receipt that I have. I got an upholstery kit from legendary and also interior as well. They sent me cotton because that’s what they say the material is for my car. When I pulled apart the rear seat it’s foam.
Is this going to change how I do the installation. I really need some advice here.