On a C box, is it an F intro, then D D G G C C F F, then repeat? So does that mean it's in the key of G?

Also, is this song known by another name?

Jamey, thank you for making me not the only person on here who get corn-fused over chords and keys.

And now introducing a brand new chord: Bb! Which, as it happens, shares a note of its chord with D; namely, a D!

If you are referring to the Aldus Roger song, it is in the key of F. Melodically, and structurally, I think it is very similar to "Mon Papa," but in a different key. You can find that done very well on Chris' CD with Louisiana Kingfish.

Yup, the Aldus Roger song. Do I have the chord changes right, Ganey? Or is what I think is a D actually a Bb?

Correct! It comes in on the Bb chord, and there are no D chords.

If your trying to play the left side bass on the C and it sounds like crap,
you're in F.
Of course, if you have a Bflat accordion,
everything will sound exactly right, except the fiddle.

JB