Keeping Stock Deck, Replacing Speakers

[mike2002]

first off, its a 2001 GLS, "rds" stereo i think...cd/tape, looks like 4x6 components up front, 6x9's in the back, not sure if its just the 6x9 but there's 2 grilles back there, 1 big one, one small sliver one

im sure i want to keep the factory deck, unless it breaks, it stays, i dont like the look of aftermarket, some day it may be replaced, so i want the new speakers to be able to handle at least 40rms (since some decks are up to 27rms now, alpine), but for a while they'll go off stock power, which is probably 10-12rms anyways, im thinking coaxil speakers up front, 6.5", but i have a few questions, i did a search but couldn't find it

whats the max depth?

there wired for components, so if i was to replace JUST the woofer with a coax, is it possible to run full range to the coax and highs to the stock tweeter? by taking out a filter or somthing? or would you recommend just using the new tweeter and disconnecting the stock one? i dont want to go components up front, i dont want to spend alot, and ive heard components need a little more power. or maybe there's a bandpass filter on the stock deck, in which it wont get any low fequencies anyways, so i might as well use a 5.25.....anyone know?

im looking for a good midbass 6.5", ive been told to go with pioneer or kenwood for this, stay away from infinity, any recomendations?

also, whats in the back? is it JUST 2 2ohm 6x9 "subs" or is there anything else, and what ohms are those?

sorry if this topic has been beatin to death, i really couldnt find it.