snapshot

Is there a difference between 69 and 70 rocker panels, other than 69 is a 2 piece and 70 is a single piece?

early shark

Yes.
The 1969 rocker moulding consists of a upper metal aluminum trim piece and a lower fiberglass trim piece. The lower fiberglass piece has a molded in section at the top edge for the metal trim piece to lay into to form a one piece appearing panel.

The 1970 rocker moulding is a metal aluminum one piece trim panel that has been anodized for its finish.

DZRick

early shark is correct.

I might be mistaken thinking you wanted to know if you could use a 70 rocker molding on a 69.

This is my brothers 69 and as you can see it has a later style rocker molding on it.