This is my first, no idea how to do this correctly so please, be gentle...
As you know there are probably thousands of these EVEREADY lanterns being thrown away because they are becoming obsolete. But a good quality LED spot light with very high brightness is is very expensive. You can do this modification for about $8 worth of parts, mainly the CREE LED and the Digital Driver Board.
Additional mod you can do it replace the 6 volt battery with rechargeable gel Cell, they fir in just right & cost about the same but you can recharge them for 500 times. this is be my next project.
This is the link to the instructional video: http://youtu.be/ITK7rCiWjq0