Thank you everyone for the responses. For some reason I could not login from my pc.
The car is a 2019 10th gen Honda Accord.
I am going to try using the auto eq function on a measurement of the factory signal in REW and apply it to my first set of outputs, loop them back to the inputs which was suggested above.
When playing with REW it doesn't like to boost anything so I used a low shelf filter to boost the low end but haven't had time to apply it to the dsp.
I will play around with this and see how flat I can get it. Then re run Dirac live.
If it's not flat enough with 10 bands of eq I think I will just buy the kicker 47keyLOC which has built in auto eq, I am unsure the number of bands.