I have used the Parts Express DSP-408 with good results. Offers a big slice of what mini-DSP does for next to no money. Experiment with that and see if you think you’re making progress. You’d have to break out the woofer input to direct couple it. I agree that leaving the rest of the speaker xover for now is a good phase 1 plan. I have also used HHHF as a resource and Tony is great to deal with. Have fun!