This will be my first 4link, but everything i have read says this should be ok. But is a 60" lower link to much?

Let me know what all you think?

Personally, from what I've read, your link design will work fine, nothing about it is wrong. My feelings on it and in general are, I dont think we need to keep the links tucked up past the frame if they are converging toward the T-Case. That is, mounts that are located under the frame like a spring hanger from a leaf spring set up are much more likley to hit and hang up on rocks then stuff that is the same distance to the ground but are in toward the center of the truck. My lowers are the same height as my T-case. But because they are pulled in toward the center, they dont hang up on stuff.