If you store them as references, you can type: "file:///" & <file location> & <file name field> & ".pdf" as the webviewer address. It will then display the referenced file. I separated the <file name field> part because you can use a field here so that the webviewer chooses a document dynamically.
I haven't tried display the pdf directly from the container field, so I'm not sure about that yet.
You could also Base64 encode the container data and then use a data URI to embed that within a web viewer.