Pelican IMS bearing stud has separated inside shaft

[WhipE350]

I'm not the expert, I've only done one of these, but I would do what Wayne said to seat the center stud then pre-test the threads with the nut to make sure it won't do what Jake is indicating could happen, if the threads f'd then start over. Make sure the tensioners are completely out and the cams are locked. I think you'll have to take those set screws out to recenter the shaft. My shaft floated around a little too but caused no issue, put thousands of miles on the car with no issues.
I think you are going to be fine, if everything goes back together as planned close her back up and drive the hell out of it. After changing mine I never think about it for a second anymore.