First, sorry for such a lame first post.
I own a 2011 Accord Coupe, 7 speakers, without navigation, dual zone climate control.
I am looking to substantially improve the sound system in the car and have chosen Focal for my speakers (PS165 and IC165), JLA 8W3-V3 Sub, JLA XD700/5 Amp. Got all of the basic components and find that I will need speaker adapter rings to mount the speakers in the doors and rear deck. The problem...I don't have a clue what thickness I will need. I've not done this in depth install before and will not be doing most of this one but wanted to have all of the hardware before the build is started so there are no lengthy delays. A friend who has audio shop will be doing the installation of the components and this is probably a no-brainer for him but it isn't for me. I'd just like there to be no big surprises for him too.
Words of wisdom from experience would be greatly appreciated.

Went to Crutchfield and that is where I found through their recommendations that these would not fit directly. I do think they will fit but just maybe need some help.

 

tell him to plan on making them out of MDF, then waterproofing the MDF with deadener (while deadening the doors and sealing the openings in the doors). plan on that effort and you will be rewarded.

 

Yep. Spare no expense on the damping cause you can never have too much. My 07 Accord, I used 1 Dynamat Door Kit on each door! That translates to on layer on the outer panel, 2 on the inner panel and 1 on the doork skin itself. If I ever win the lottery, Ill pay somebody to yank out all the interior and lay down a couple layers of Dynamat on everything.

 

I will be dampening and sealing the doors and maybe some day doing the whole interior of the car (waiting on the lotto LOL ).
Also putting Focal coaxials on the rear deck along with the 8" sub in enclosure. How much deadening do I need for the rear deck and trunk?
I'm not going for any competition type setup; won't be moving a large volume of air. The rear deck speakers will also need spacers for the speaker mounts.

Will be starting the install on Tuesday and plan to get at least the major part of the install completed by Wednesday. I drive 35-50K per year and can't be too long without the car. Spending that much time in the vehicle though, I want to enjoy my music as much as I can.

 

Skip the rear speakers. They do nothing but degrade your overall sound quality. You can take the money youd spend on those and put that towards better front speakers. Thatll do a whole lot more for improved sound quality than front and rears.

As for deadening the trunk, I never really have. Ive always been a sound quality guy so Ive never listened to bass heavy music and never had the need for a dead trunk. The only time that really comes in handy is if youre listening to rap and dont want your license plate rattling around or are going for the most maximum output level as a really stiff trunk will keep it from flexing and can add a db maybe to the output. Overall though, its not really worth it. Its fine and dandy if youve got the time and the money but if not, its best to put that cash towards more important stuff like speakers and amps.