Agreed. That pretty much what the short article I posted said. The more modded the more benefit.
I'm amazed your temps are that low. It means your t stat isn't even opening most of the time. My ECT's normally stay right at the fan hi lo settings. When I had the Stage 3 Rad 3 fmhe, during the summer with the AC on it would climb near 200* when hiway traffic would slow during rush hour.