Display highest value from checkbox selections in gravity forms

I have a form on my site with a multi-select checkbox list. Each item in the list has a number assigned to it (some are duplicates). I want the user to be able to select multiple options from the list, and for gravity forms to collect the highest number selected.

The reason for all of this is I have multiple confirmations that display different options using conditional logic based on the highest number selected. So if the user selects 3 options all with the value of 1, the form will return the confirmation of 1. but if they select a 1 and a 2, I want it to show the result for 2. gravity forms just finds the first value selected and uses it as the result. (in this case, 1)

If anyone has a fix I greatly appreciate it. Thank you.