Don't think you'll see many if any door mounted subwoofers.
Most hard core DIYers have a hard time getting rid of rattles with 8" midbasses... so a subwoofer IB in the door?
Try to search for an install with 8" Phase Linear Aliante
It's the only install I know that uses a subwoofer in the door HOWEVER they are not IB but sealed...
Now I am looking at a restored jeep renegade and am trying to figure out how to implement them in kicks and still go three way or kicks as sub enclosures? I dont know....having a hard time shopping for a new vehicle?
Restored international scout, jeep renegade (80s) or restored dodge ramcharger?????? The charger offers the best audio solution, jeep offers the most fun, and the scout offers the coolest cool factor? Hard to believe my truck can melt to the ground, ruin my center console enclosure, but those 8s are still ticking????? If thats not an advertisement then I dont know what is! New Alpine Type R's......Almost fireproof