Whatever you choose to power them optimizing the internals of the speakers will increase the apparent sound quality by as much a 50%. Putting in the best polypropylene capacitors (top Wimas are recommended) & Vishay resistors will do wonders. Better audiophile wire as well. Klipsch in the 70s put monster cable in their production speakers which meant it was Paul Klipsch's idea. Don't know how that progressed but it clearly points the way. You may need to double up on caps for their values to match what's in the xover. That might mean an exterior box. One thing's for sure, you'll be near staggered by the difference in sound quality.Actually, I'm looking seriously at doing the full crossover upgrade from Bob Crites. Not fully committed to swapping out the squawker and tweeter, though there are compelling cases to be made to do so.
I'm definitely more into the idea of a fully assembled replacement over risking my poor soldering skills defeating whatever gains I was supposed to make replacing caps. :)