audiosense -
There are three ways for you to go I think:
1 If you want to try inexpensively, update any caps in series with the tweeter and midrange.
2 Get a miniDSP and attempt to EQ your tastes into the speaker
3 Get a brand new kit.
The hardest thing for newbies to do is take an old speaker and switch a single driver. It's a lot of work, and may not be worth it due to the quality of the parts involved in the original, the cost of the new crossover, etc.
This is totally a great learning exercise. You will learn speaker measurement and analysis, you'll get new tools, and be able to dial in exactly what you want, but .... it is ONLY worth doing if you want to invest in yourself that much. To do it to reuse the parts you have, not really worth it at all.