Savage Worlds - Cannot change the Attribute which maps to a skill

Afternoon, This issue came up in our SW-PF game last night, one of the group created a druid character that uses Spirit for the Survival Skill (Nature Sense) as opposed to the normal Smarts. I couldn't see a way in the sheet to set this to be the case.  I snipped Survival and Athletics below. Athletics has a limited drop down to swap between Agility and Strength which accounts for the 'Brute' edge. It may be more flexible to allow the Attribute to be manually set for a skill if needed. I cannot see a way to adjust Survival at all.  

Up until now, this was not needed, but I'll work on getting this fixed.  In the meantime, if it's important, a work around would be to add a custom skill, call it Survival and link it to Spirit. To be clear, that image is for a custom skill...