If your not air cooling your bulbs then you don't need to put it back on if you don't want to waste the time (just save the glass until you do air cool). On my hoods putting the glass back on is a pain in the ass. You literally have to remove the frame around the glass, get everything aligned back on right, and then hope and pray the holes on the frames match up to screw threading...otherwise you have to start over till it does.