add amplifier and tweeters to stock radio

I have a 2000 Nissan maxima SE. I want to install a California 4 channel amplifier to the stock radio. I'm planning on using channel 1 & 2 for two tweeters and ch3 & 4 for a box with two tens.

I also have a MTX cross over which takes high, mid and low input. I will only be using the high and low input of the crossover.

question: my radio does not have any rca pre-out how do I go about getting the signal from the stock radio to the high and low input of my crossover?

Do I need a line driver, line level converter, line output converter, line out converter...etc?

Also does anyone know the wiring diagram for the radio, I'm having trouble finding a wire for amp turn on (remote). I tried to use the radio Illumination but that did not work. I only want my amp to power up when the radio is on.

You gest have to try one wire for each chanel (l and r) and conect them to amp input. Put the level on radio low aswell as  the amp .Most of radios do not have a minus to the output gest have two wires for each output so one of them must be your signal neded for amp.

2000 Maxima Stereo wiring

You almost always only use crossovers when you have multiple amplifiers.  I'm guessing you have a profile amp?  what's the model number?  and what about the model number of the crossover?  If you get me that info I can give you a more exact answer.

Most likely you're going to need to get a 4-channel line output converter (or two 2-channel converters) and tap in to the speaker wires in the radio's harness.  Each speakers' wires will correspond to one RCA plug, so since you have 4 sets of speaker wires you'll have 4 RCA plugs.  Assuming your amp is a 4-channel amplifier, the two plugs that are hooked up toi the converter that's tapped in to the front speaker wires, will get hooked up via an RCA cable to the amp's front signal inputs.  Then do the same thing for the rear channels.

Does this vehicle have the bose sound system?

no this radio does not have the bose system

Amplifier: California profile series 400 watt

crossover: MTX RT-X02A

2 RCA input front and rear with the parallel crossover.
2 high pass front and rear with 1 low pass (Subwoofer) crossover points output, continuously variable from 32Hz-400Hz.
Selectable bass enhancement circuit (0dB or 12dB at 45Hz) with Three continuously adjustable output gain controls on each channel.
Signal to noise ratio >96dB and >.05%