Dynamat on floor and doors really make a big difference

[lateralis]

One thing I've learned over my years of doing my own vehicles deadening is not to go overboard. Does it sound great short term? Absolutely, a fully deadened vehicle is something else. What I have found though over time things like MLV or other foam that you've placed around start to deteriorate. What I've seen is the foam gets hard or crumbly after a couple of years. This leads to plastic rattles from random panels you now need to hunt down and try to fix. Usually ends up having to replace all the foam in the affected area. Another thing is fully sealing the doors. I've had to go back into doors over time to say fix window motors or a rattle and with a fully sealed door it's a huge PIA. Now you got new holes you need to plug up since you ripped out the deadener that was in the way and if you just put more on to seal the hole you could run into the issue of it being to thick. Now your door doesn't go back all the way or some other issue. With all that being said I personally adopted a more minimalist approach. Sound deaden only what you absolutely need to. Directly behind speakers. use cloth tape (the stuff the wire looms inside our trucks are wrapped with) or soft Velcro under plastic tabs to reduce plastic rattles. If you want to seal the doors, do it in such a way that you have removable panels. This makes access to the door interiors a lot easier. I like to use nutcerts and bolts to hold a panel in. I've seen the ABS way and the way over the top way with fiberglass panels. Both are good for sealing as you can throw a weather strip on the edge to help seal it and get an exact fit to the door. ABS just needs a heat gun to get it to do what you want. The nice thing about a fiberglass panel though is it a lot stronger and helps stiffen the door up. This also means you would need less deadener on the inside door skin to stiffen it up. All in all just have a well thought out plan before you rip into it. You don't need all the extra stuff to have a truly nice setup.