I will admit I was under the same impression as Ryan until I spoke to the guys at CDT they recommended moving my tweeters or disconnecting them because I was running the front stage tweeters and the front center channel system I really didn't need tweeters high up in the doors
You only mount them close to the mains if you can put the mains in the proper place. Still don't understand what's so hard to follow about that? you're not putting your expensive speakers in the kick panels in a Land Cruiser. Booger already said his mains are in his door at knee height. So you would say eh it's already effed let's just eff it up some more and install the highs 90 degrees relative to the listener were they are as completely out of phase as possible? Or since this isn't a completion car the components are going to be mounted in locations that make sense for a Land Cruiser would you like to offer legitimate suggestions on where to put them? Even Lou who says he understands they should be closer to the mains, has his in the door turned off and at ear level.
FWIW....and I'm a hack at the car stereo stuff compared to where alot of this is (luke's install) --- I mounted tweets to the sailpanel / black triangle.
With the headunit tweaked it's good enough for the girls I date.
Duct tape 'em around a bit if you are invested enough to try something fancier than the door/sail panels, see where the sound is what you like???
It's like I took my hand off my mouth while talking. Sooooo much better.
The guy at the stereo shop I snatched some RCAs from was very familiar w our trucks, claiming factory speaker locations were part of it's water fording capabilities, lol
Kick panels are ideal in most cars for sound stage. If all you care about is volume then by all means put them on the a pillar. When I finally get around to doing mine I'll probably just use the factory locations which really aren't ideal.
If you want to try different locations for your tweets, just put some weak double stick on the back of them. Use that to temporarily try them where you think you want them so you can see how they sound.