Need help with endlink size!

So I'm in the process of pulling all my suspension components out and replacing them if needed before the lift goes in. My rear end links were garbage and I need to order new ones. Here is the issue...everywhere I look it shows the end links for my truck (2006 F350 SRW) id need a 7" and some change end link. This is for it being over 9900 GVW. Which all seems correct. However! The ones I took off the truck were the 13.7" ones that I've only shown sold for dually's. I'm stumped and not sure what to order...anyone have a solution???