I have basic audio system there are a few people replaced just the rear door speakers for the upgrade, but I did not see anyone do the same for the front/tweeters. If I just want to keep it simple and replace the front speaker and tweeters, what is the best approach? can I just replace the frontal midrange driver? If I want to replace both the midrange and tweeter, do I have to use the aftermarket crossover? I know the location of the front door speaker cables are located under the side panels, but how about cable for the A pillar tweeter?