The crossover was changed to match the new tweeter. I believe it was said there would be soldiering involved in replacing the crossover. There was some discussion about selling the upgrade parts, but no price was ever settled upon--at least mentioned in the board.

If you're serious about doing the upgrade, you might try contacting Axiom directly.

Pioneer PDP-5020FD, Marantz SR6011
Axiom M5HP, VP160HP, QS8
Sony PS4, surround backs
-Chris