For the groove I would follow the advice of jjjaos. About the tongue you may permit tolerancing up to 0/-0.001" because easier manufafacturing and measuring. In this way you will accept the advice of gearguru, because the ISO system of fits offers fit like this.
Good luck!
I design my gears by means of Solid Works 2001 Plus with Add-in Mech-Soft. The gear-model has a real involute flank and this is sufficient to me to be happy.
Regards