Big 'ole adjustable wrench and some man power is what is making mine hold tight. It is about a 45-46mm nut on there, haha. Pretty massive.
I would say Indy4x adjustable lower links. I have the adjustable lower links and the adjustable upper link, gives you great options when setting up pinion angle and dealing with driveshaft issues, and there is no way you would ever break one. Always better to have more options, and the adjustable links are perfect for that, and it gives you more grease points to quiet your ride down.