Not sure I understand. There are adapters and installers that can make just about anything with the correct depth fit in the door. Bass is not directional, so the woofer can be placed in the trunk.

Will Bose system fit in non-Bose car
 

Decided on hertz ESK and ECX 165 for the doors 12" sub (didn't get the model #) for shelf all powered by a 5.1 JL amp and may have to bite the bullet on a bit ten d (PRICEY).

Will Bose system fit in non-Bose car
 

Hertz sub that is.

The bit ten D is worth it.
It will also clean up the factroy signal and give you a nice clean signal for your amps.

I love mine.
I'm using the optical output from my Nexus 7.

Does the factory head unit just plug into the bit ten and do you still retain hands free calling?

Will Bose system fit in non-Bose car
 

On a scale of 1 to 10 where one is a clock radio the BASE SYSTEM would be a fiveish if I bought the component speakers for the doors would the sound quality improve to a six or drop to four or three given that there is no Bose amp to go through?

I don't think it has enough watts to push some good speakers neither does a bose head unit. From what i know and owning several bose systems the head unit is just a rebranded radio made by clarion or some other OEM. The additional sound gained from a bose is done with the bose amp not with the head unit. One time my bose HU quit playing cassettes in my 94 maxima so i went and had a sony head unit with a bose adapter installed and it still sounded the same maybe a little better with the sony. Bottom line the head unit means nothing. It's all in the amps. Serious, take a look at a stock bose speaker. It's just a paper piece of crap and easier to push with less watts.

You splice into the factory speaker wiring for signal.

You can also splice into the factory power wires.
The install isn't to bad if you have installed an amp before.

Not sure about the handsfree but it should work the same way.
The bit ten d works as a line output converter in this case.

If you are going to run a decent set of speakers, it's worth it to invest into an amp(s)

The bose is ok overall but nothing special.

If you are just going to drop in speakers, I wouldn't spend more than $200.

Ok, but I don't have Bose. Was going to get the Hertz ESK for the front door to pair up with the BASE system. Later get BTD and JL amp to run all. May just get a sub and amp. Does anyone know the sub hole size in the rear shelf?

Base or bose...either way I would get an aftermarket amp.

The rear deck can handle most 10" subs. Its not a perfect circle.
Some mdf and a dremel will easily fit a sub.

The issue is with the sub running free air. Just make sure your sub can run free air.