Just my opinion, but I feel there are too many subforums already, and while the '18 is a bit different, it's not dissimilar enough to warrant its own subforum.
Same issue for me and I have posted about it before-- noticeable clunking only after installing the red differential bushings. I can only imagine how much worse it would be if I had used the black ones.
As for the stripes, I ended up going with a vinyl spray type striping, like a professional PlastiDip kinda thing. There's a lot more color options than precut vinyl. Mine is called Stormcloud Gray.
Got my jacking rails delivered, but haven't had a chance to install them yet-- can't wait. Ironically enough, I'll have to jack the car up to put them on, I think...
Here's the thread in question:
http://www.mustang6g.com/forums/showthread.php?t=39090
No, there's no "hard evidence" but there are real world examples-- not just some guy's mechanic telling his gardener's maid's brother-in-law.