Convert 2 mono tracks to stereo without converting rendering possible?

I have 2 mono tracks from 2 mics on a piano and simply want to combine 2 mono tracks into 1 stereo track without converting, rendering in a way that could affect the sound quality.   Is this possible and how is it done?   I have Sonar X1 Producer Exanded..

Martin, forgive me if you already know this.
Your mono tracks are automatically centered in the stereo field. Simply bouncing them to a stereo track will result in a monophonic track that takes up twice the space on your hard drive. It will not give you stereo sound.
There must be a difference between the left and right. Stereo is essentially two mono tracks, and relies on that difference to create the illusion of space.
Personally, I wouldn't sweat the bounce. Pan one track 40-70% left, the other to the right an equal amount.
You may want to apply slightly different EQ to each, but that is a judgement call.
Unless you have a specific reason for a bounce at that point, I'd let it ride until the final export.
Just my thoughts. We all have different ways of doing this, so find a method that works for you.

It isn't necessary to convert the piano tracks to stereo. In fact, leaving them mono has some advantages. However, bouncing them to a stereo track will not impair their quality in any way.