Front components are 6-1/2 to 6-3/4. Rears are 3-1/2. I own a Base model so no Bose sub for me. You should really consider this micro sub as well. I upgraded my Bose to aftermarket on my 350Z and the sub enclosure vibrated/rattled pretty bad at higher volumes with the new sub I added. That poor Bose sub popped and cut off about a quarter of volume on the deck and amp I had installed so I had pretty much no choice but to upgrade the sub. Bose systems cannot handle wattage at all so dont waste your time in keeping any part of Bose in your car if you are upgrading.

Yeah i have been doing my research and almost everyone on here says its all crap. I do like that micro sub it looks to fit an 8" sub which is plenty bass for me now what i would like to know is where would the enclosure go? In the summer i do daily my z so i need as much trunk space as possible.

A lot of good advice flying around this thread. One thing I can tell you for sure, the bose sub absolutely has to go. that poor thing can barely take the few watts the bose system throws at it.
A hint of what your looking at budget-wise will go a long way to anyone pointing you in any kind of direction. I mean, were looking at many components all of which can run from $100 to well over $1000 each.

Well if i can spend $800-$1000 max for a good system i will be a happy camper.

I'll give it some thought, and throw a couple ideas your way

ok thank you i would really appreciate it. if this helps out.. im looking for a real crisp clean sound that gives good detail. also some bass would be nice but not over powering to the point were my heart feels like its going to pop out of my chest.. also no car shaking either lol..
also i listen to all types of music but mostly rock, alternative rap hip hop.

Keeping it in your budget range...
Head Unit Pioneer AVH X2600bt Crutchfield $260 8 channel eq built in bluetooth
Amp Alpine PDR-F50 4 channel Sonicelectronix $310 85watts x4 or 85x2 and 250x1
Components Image Dynamics CTX65CS Amazon $230
Sub Alpine SBR-S8-4 Amazon $150
$950 Gets you down the road smilin'

^ What he said! Our bose system is a basic set up. Anything you swap out is an upgrade. I like Strada, Dynaudio, and Focal for speakers. Audison, Mmats, McIntosh, Zapco for amps (if you can find a pristine condition Art series PPI, Phoenix Golds, 1st gen Xtant, or HCCA Orions go for it). Choosing components is the easy part. Killing noise is the hardest.

Don't forget to add good cables to your budget.

looks like a good setup. my question is where would the enclosure go and also if im doing a complete overhaul should i put in better speaker wires?

i was thinking about the cables aswell. they probably arnt all that great maybe what 16awg?

Sub enclosure should fit nicely on the parcel shelf behind either seat.
A decent quality 4 gauge amp wiring kit should have everything you need for amp and speaker wiring. You will need to get an extra set of rca cables to run back for subwoofer channels.
Most of the newer electronics today are far less likely to leave you with noise issues like they were in the past, and even a set of rca cables at the lower end of the spectrum has adequate shielding against noise induction.

I forgot to mention.... The alpine amp will fit behind the other seat

so it should be a nice clean setup then. is there a brand or type of gauge wire/ rca wires you recommend? also do i need brackets for the speakers seeing as they are 6.5?

DB Link makes some reasonably priced 4 gauge amplifier kits,
As for RCA's, scosche, stinger, and monster all make decent sets.
Try looking at amazon.... hundreds to choose from, and many reviews to read as well.

For the short runs involved (3-4'), you can go as small as 22 ga with 4 ohm speakers (search for speaker wire sizing for details) but I usually use 14 or 12 ga where space permits. Heavy-duty lamp cord (zip cord) works well and is a lot cheaper than the stuff that is labeled "speaker wire."