I have a rough stereo mix coming out of Sonar X3E to the master....all good.....but I want to lay down an additional guitar part......it is Pod HD to Vintech X73i to input 3 of UCX.....I do not want to monitor the guitar part from the stereo mix....I want to run a separate output for the guitar to a hardware mixer that I use for monitoring so I can control the monitoring volume independent on where it's set in Sonar......I cannot get Totalmix to comply even though this can easily be done....Help!
Thanks!

You are right this can be easily done.  So you must have a routing issue going on.  I am not entirely clear how you are set up so it is hard to say for sure.  No offense meant, but do you know how to use Total Mix?  It can be a bit tough to figure out until you understand the basic signal flow. If you are not comfortable with TM I suggest looking at one of the intro videos put out by Syntax.  If you already understand the basics then a more detailed description and screen shots can help identify the issue

In Total Mix, click the output you want to raise the guitar for, then you will see that output indicated under the faders on the input channels. Raise the fader on the input channel and the level will rise in the selected output channel.
 
F1 opens the help file.
 
Total Reset is pretty useful to know about >> I think it's under options.

You choose the output on TotalMix and then adjust your input slider up or down as you want it. The first thing you need to remember is that total mix adjusts whatever output you are working with or is active in TM.

Possibly there is confusion because you also have input echo on in Sonar on your recording track (sending the guitar to the stereo mix output. Make sure the track is only armed and doesn't have input echo on.

Thanks everyone.......I never use input echo......I figured the problem out.....I have to say I really like TM.....I'm using 4 of the outputs to run 2 pairs of powered monitors.........Quick question for the guitar output......I usually leave the faders at unity gain and adjust recording volume from the preamp source

I usually use the auto-level feature for 1/2 hour or so then turn it off if I remember to. I don't want someone bumping the mic to reduce the levels. I do use the faders to adjust the levels, not the input gain. the input gain is important to ensure you get enough signal to record all the sound. You don't need to push the head room at the top to come close to clipping, but there's no good reason to be lower than necessary either. Use the fader. It's there for a reason. :-)