FISHER GRANDPA - GLASS DOORS????

The entire stove is designed differently with glass doors.

Grandpa solid door stoves are built for solid doors only. Only a screen is used to view fire. You can't put glass doors on any stove not designed with glass doors. The air inlet must be an air wash system with glass, so the incomng air keeps the glass clean. If you have solid doors, the air intakes are on the doors. Glass doors have no intakes on them.

There was a Grandpa III and Grandpa IV with glass doors. The main air intakes are on the sides, and air wash for the glass is below the doors.
Notice the older III model has flat top, smaller glass than the IV below.

Model III

Model IV;

Notice air intake draft caps on sides, slider levers for air wash in front.