Hi Bill -
1) Duplicate your global picklist as another global picklist or just object level picklist with the reduced set of options
2) Use a UI only field as Raymond describes hardcoding the 40 items in your Skuid page instead of in another global picklist. I would not recommend this approach just due to maintenance issues but technically it should work in combination with some action framework update field actions.
3) This one I'm not sure of and I've never tried myself but I think it will work - Use recordtypes to restrict which picklist values are eligible for fields.
Hope this helps!