Here are my measurements with only crossovers and no EQ at all. (Audiofrog GB60, GB25 and SEAS Tweeter with a JL 12W6V3 sub in a stealth enclosure)
The tweeters are in pods on the a-pillar and are cut 8db for driver side and 5db for passenger side
Acoustic XO targets are 80-300-2600 LR4 that will be tuned to a JBL curve modified with a bit of extra bass.
Electrical Crossovers (set in the dsp):
Sub 70Hz LR2 LP
Driver MB 70Hz LR4 HP and 300Hz LR4 LP
Pass MB 70Hz LR4 HP and 350Hz LR4 LP
Driver MR 300Hz LR4 HP and 2600Hz LR4 LP
Pass MR 350Hz LR4 HP and 2600Hz LR4 LP
Tweeters 2600Hz LR4 HP