you could get the hypex plate amp or mini dsp plate amps. You will need to find a way to mount them either into the cabinet or onto it externally. Then you start tuning the speakers. You select various slopes, crossover points and time delay. You compare the results by ear. You adjust the eq too. You will need to put in a bit of baffle step compensation and a gentle downward slope.
Yes you bypass the passive crossovers.
Yes you bypass the passive crossovers.