K frame splash shield differences

I've been looking at trying to close out more of the openings on the front of my 67 Dart now that it's seeing more commuting service, but I had a question regarding the K frame splash shields. I see there are ones listed for pre and post 73 cars, but I'm unsure where the change is. They mention a single vs double angle on the bottom or something like that, but I wasn't sure what drove the change. The main reason I ask is that while my car is a 67, I have a 73+ K frame in it for the spool mounts. I know the 73+ also ran the sway bar through the K frame (which I could see altering the splash shields), but I kept my existing front mount bar by drilling out some holes where it used to go on the earlier setup. So long story short, which splash shields would I want to use on my car?