Jim speaks the truth. I've built a couple of 2-Way projects and have been designing a 3 way project for almost a year now. Getting the drivers from AudioJunkies threw a wrench in the design, but still 3-way is hard to do with out knowing exactly what you are dealing with.
However, honestly with the "woodies' project the speaker drivers themselves aren't the type quality you would write home about. So, they would probably benefit from a specific designed crossover
but not that much.