Alright I just used "Invisible Glass" cleaner all by itself yesterday (2 coatings. spray on, sit for a few, wipe off) and it seems to have cleared most of it off. It rained again today and I can't really see any more spots of gunk like I used too when the wipers go over it.
There's still a small amount of film left but it might be from the wiper blades because I forgot to wipe those off. When I wash my truck this weekend after the rain stops I'll be sure to wipe down the windows a few more times with Invisible Glass.. so for anyone wondering the same thing on how to get rain-x off.. the stuff seems to work.