EQ questions using guitar amp with bass speaker

[Fndr8875]

Ive been wanting to build a noisy cricket amp for a while, but i put it off bc i didnt have a proper speaker cabinet for it. Well i picked up a small 10 watt bass amp, Kustom kxb1 is the model number . Got it for 10 bucks, and its practically new. I figured ok i can take the speaker out, and put in a 6 1/2" jensen mod and either take out the chasis and use it for housing noisey cricket, or use a hammond enclosure. Well i built it yesterday, i found a 1590bb i had forgotten about that was my first enclosure and was not laid out good for a pedal with the drilling, I also used the radioshack ic boards beavis did pdf of. And to top it off massive radioshack 100k,10k,5k pots from a while back, switch is a spdt, from radioshack as well, and giant. So box is crammed full, i was skeptical that it would work, or that i would even attempt to troubleshoot. But i fired it up and it works perfectly no hum, hiss , everything works as advertised. I am going to order a speaker and just use the cabinet, as well as the chasis, it will match up pretty good, there are four knobs on the amp, anyway back to original question, Im questionoing if all this is nessesary the speaker actually sounds 10x better than when guitar is using bass amp plugged in, can anyone suggest a mod that might make it sound even better? 100k linear tone knob with 100nf cap. Ive taken amp apart and it uses all 50k linear pots, would maybe a 500k linear tone pot help, or a different cap, Ive got another radioshack board as they come in a 2 pack, im hesitant to pull the one out of the enclosure as it just doesnt seem sturdy with so many caps one leg soldered onboard an other soldered to wires and such. Im not familiar with EQ ranges and how to modify them. Any way Ive got some pics if anyone is interested.

[anotherjim]

C2 on the Beavis scheme' - 47nF is a bit small for bass. It could be 470nF to get down to 33Hz. This could show up shortcomings in the power supply, so power cap C1 might need increasing - maybe 1000uF - OR lose a bit of (potential) low end and have C2 at 220 or 330nF.
Similarly, output cap C8 could be bigger (470uF assuming an 8ohm speaker) - but here's the rub, what impedance is marked on your existing speaker? A lot of small solid state amps use 4ohm speakers. I for one wouldn't use a 386 with less than 8ohm speakers, but I've never tried 4ohm.