For you cats dead set on learning the Parlar Trick Perrodin Two Step. Let's take away all the distraction and learn it the same way Steve Riley probably learned it. Let Tony "The Dewey" Balfa play it for you and you can follow on your "D" accordion 1st pozish pushing mostly.
After you get that down, switch to your "C" accordion 1st pozish pushing mostly, and play along with Austin Pitre. Let that loud base beat in the back ground keep you on track and in rhythm. Spend about 2-3 hours with both videos for good muscle memory.
Remember, the Perrodin can be played using only buttons 5,6,7,8. Then you just search for their sister buttons and play doubles whenever you are able or when doubles obviously apply. Persistence pays off. It also helps if there's no one in the same house with you when you begin to learn this song, for they will grow to hate it pretty badly, while you grow to love the way it makes you feel when you play it. Like a great big beautiful PEACOCK! hehehehe.
Just messing around...Tony was that not so famous Balfa that was usually seen beating on Dewey's fiddle with those sticks. Very obscure fellow don't you think? I wonder why?