John's solution is the easiest way to go.

If you want to use your hybrid in a lot of songs, look into defining a multistyle. Using a multistyle, the style is defined by using the part markers. In your case you would define Floyd as a/b and Travis as c/d. Changing from one to another is only a matter of setting the appropriate part marker where you want the change.

If you want to try this, it is easy. I recommend making backup copies of your styles before editing.

Edit the style Floyd. In the Misc settings, put C_Travis as the Multistyle. Save your style (preferably to a different name). When you load your song with this style, it will now have a/b (Floyd) and c/d (C_Travis) part markers. Set those where you like.

R