I made a Spice model of the Bench crossover your PCB is based on.6DJ8 Tube Crossover
I put a few more components in the circuit model to provide horn compensation, but the Spice model is easy to modify for whatever crossover points and what-not. The OrCad schematic that the model uses is nice too. I don't know if you're interested, but if so, feel free to link it on your website.