B5 Crossover Question

I have a B5 crossover that I'm using with some open baffle experiments. I'd like to try this xover with my horn setup but I need a 500hz crossover point. Is there any way to modify, or clip lead some resistors in, to provide one extra or modified high pass/low pass xover point of 500 hz?

I know the B4 is what I need but just trying to use what I have.

Thank you Nelson. This is good to know. To make sure I understand, I see 8 Wima caps that you are referring to. Changing these to the value you give above will revise the B5 to have crossover frequencies adjustable from 40hz to 600hz in 40 hz increments? This would make this crossover much more useful to me!

This is another great product.

The 4.7 nF caps on the high pass filter would be changed to 2.2 nF and
similarly on the woofer low pass filter, 4.7 nF to 2.2 nF This will essentially
double the crossover frequencies given by the switch positions.

The 8 caps in my B5 are labeled 0.047 which I assume is uF. They also match the Wima specs dimensionally for that value. This is 47 nF and not 4.7 nF, correct? Am I missing something?