I have read and study the last few days trying to learn as much as I can before I start asking questions. I feel like I have this set up but want to make sure.

I set up my cameras 1k tone to be on, and when I to the Bars the auto levels go to -20, The level bar goes -40--30--20-10-0 0 is where the red line is. So this is giving me quite a bit of head room.

When I do the same on the mixer, the led lights go to 0 and the -20 mark on the mixer is hardly registering.

So I am assuming that I need to shoot for 0 on the mixer, and -20 on the EX1r is this correct?

Well after doing a few tests, -20 sure seems to be pretty low, -10 seems to be better but am I getting to close to clipping?

So I am assuming that I need to shoot for 0 on the mixer, and -20 on the EX1r is this correct?

I don't quite follow you Denny, Are we talking program audio level or test tone? (a.k.a., reference level).
What kind of mixer and meters: VU, Full Scale or other?

Why are you using the camera's test tone with an external mixer and bringing 'auto level' into the equation.

Rick, thanks for trying to help and sorry I am so clueless to audio, I am really trying to educate myself.

Ok, everything in the camera makes me think it is shooting for the scale or meter reading should be -20.

The ex1r has an option to turn on a 1k test sound when you select the bars signal. When I turn this test signal on, it goes to -20 on the internal audio meter.
Also when taping and setting the audio to automatic, and having a controlled audio source it attempts to keep the sound level meter at -20, leaving -10 and 0 before it peaks.

When using the Sound Devices 302mixer, it also has a test signal (1K) and when I turn that on it lights up the green led's and the first red led which is "0"

So I am assuming that my goal should be mixing in signal to the "0" led, just as it starts hitting the red led's and set the camera volume control to where the input from the meter is at -20 on the audio signal scale inside the camera.

It is a little soft but the more I play with it, I think I have been pushing for too hot of a signal, and why when loud clapping, or DJ blasting away, I sometimes get some clipping.

I just do not want to not have enough volume recorded, if that makes sense.

[i]
Why are you using the camera's test tone with an external mixer and bringing 'auto level' into the equation.

I checked the cameras test tone to see where it landed on the cameras audio signal scale.

I used auto on audio to see where it tried to keep the signal, and it tries to keep it at -20. that is where I came up with the -20 for the volume level in the camera, just seems thats where it tries to keep the volume level when set to auto.

Normally -20 or -12dBFS is the desired reference (test tone) level.
On the SD-302, set the test tone level to 0dB (which is the factory default) Then set the camera's input to 'Line', set the cam's meter to read -20dB. This means you should be able to output close to +20dB (peak reading mode) on the 302's meter without clipping the cam's audio. I set the 302's limiter's threshold @ +14 to +18dB depending on the anticipated audio. Some folks set the camera's reference level to -12dB which yields a 'hotter' overall level in the cam, but with less headroom and increased risk of clipping.
Theoretically, and in a perfect world, for optimum dynamic range (using ALL 16 bits), your absolute highest program peak would hit 0dBFS, . (anything exceeding that would be clipped) However you must maintain enough headroom for unexpected peaks. Typically, I like to be hitting around -10 to -6dBFS on a camera or audio recorder, which allows (me) adequate headroom for peaks, with some additional safety from the 302's limiters. However I watch the meters diligently and ride gain for higher/lower SPLs. ( but I don't have to worry about shooting)

As an experiment and/or to gain insight, you may want to employ the 302's "Full Scale" method of setting up the mixer/camera gain structure.

Thanks Rick, I am going to do a lot of testing, I know I will not go back to working with out a mixer again, just much harder on me to keep the audio where I want it with out a mixer.