The super brite blue and white LEDs have come down in price a hell of a lot recently. AND they are actually bright.
Hmmm IF those big old storage batteries do not have plates that are warped PERHAPS you could get some cheap Bright Blue LEDs and fix up a few LED Reading Lamps powered by those old batteries. IF the battery is in half decent shape capable of putting out 6 volts you can power most LEDs. If I understand the size of those batteries and the low current drain of LEDs you could run a reading lamp a hell of a long time between charges.
