"We need to play with that a little bit," Ronnie Dunn tells PEOPLE ahead of their Neon Moon Tour kick off in March ... she remains in a state of mourning over the demise of Rascal Flatts.

Their newly announced dates are just the first leg of the Neon Moon Tour, which is expected to extend in the months ahead. Over the years, Brooks & Dunn have enjoyed a plethora of hit singles ...

"And he calls from his bus one night and he goes, 'KB, they're doing this dance for 'Neon Moon,' there's over three million views on this ... and the label just called and they said if we'll do ...

And as a slew of Texas musicians from a wide array of genres have discovered over the past few years, we already know what it is. It’s Brooks and Dunn’s 1992 country hit “Neon Moon.” ...