Upgrading the caps and resistors would be a good idea if you want to stay with the original crossover, However, some folks like to use an external crossover. Whatever your choice, upgrading the chassis wire and binding posts are a must do. There was an upgraded 48" ribbon available at one time, but I'm not sure if it still is. The woofers, leave them alone. I don't know what you're using for power, but they do benefit from tons of good clean power.
You might want to check out www.carveraudio.com for more info.
You might want to check out www.carveraudio.com for more info.