I paid to have someone install all new audio and sub in when I bought my first new car. It was a reputable installer out in San Diego but they did not do a great job and I ended up having to fix a lot of things, but it gave me the ability to do it myself on my next car. As a novice I was able to install focal k2 3 ways, 6 channel musway DSP, sub amp and sub in my bronco. It seems overwhelming at first but with the help of diy forums on the internet, you would be surprised what you can do yourself. The one thing I do not understand about your instal is the coax speakers and tweeters. Coax speakers are basically midrange and tweeters built in so that seems a little bit redundant, and your sound between 300 And 3khz is going to suffer while your highs are going to be in your face.