Hello, This is my first post, thank you for having me. I look through the site before asking on the forum but I cannot seem to find my specific answer. I have procured 2 different types of B-Billar's for my 81'. The first I got from Fbodywarehouse it came as a pair for the left and right door (Looks like a single blade with no grooves or extra molding). The second set I got from a private seller (it has grooves to put the weather strip in I believe). It seems that the ones I got from FBODY are not a two piece part per door. How am I suppose to be installing this? Should I install the ones from FBODY by themselves or do I need to have 2 pillars per door? Pictures will make more sense. (Do they go together?) Do I only use 1 of the sets? Which set should I use Ive seen it so many different ways?