This is probably not that easy to do yourself, but below are a couple of suggestions:

From a logistics standpoint, it probably makes more sense to do Iguasu before/after Rio, as the falls and the Amazon are pretty far from each other

Amazon:

http://www.anavilhanaslodge.com/wordpress/en/

Falls:

https://www.belmond.com/hotel-das-ca...iguassu-falls/