Hurst shifter box too much play?

They do have shims between the levers that wear with lots of use.
Check that the top main pivot bolt is tight. It can loosen up and make a wore shifter
seem worse than it really is.
Although not as correct as replacing the worn shims a person can file or grind a small
amount from the end of the spacer sleeve. This is the one the main pivot bolt goes thru and aligns all the levers.
It can also be reinserted the opposite way and have a new wear surface for the levers to work on. A way to wear a different area of the spacer to get more life from the part.
These two no money tricks can extend the life of a very wore shifter for a long time. Just be careful not to grind to much from the sleeve or it will lock up when you tighten the pivot bolt. This sleeve and the cover plate is what sets the width of the shifter box. Of course if you make this space to small the levers will be to tight.