Hi @dmac73,
This is not a simple process - I have an app that does exactly what you want and will share the specs so you can apply it to your requirements.
Firstly at App OnStart, I have this
Set(
stSite,
"https://xxxxx.sharepoint.com/sites/xxxxx/xxxxxDocs"
);
ClearCollect(
colDoc,
xxxxxDocuments //this is the SharePoint Library Name
);
The Items of the Gallery are this
Sort(
colDoc,
DocName,
Ascending
)
The View button on the Gallery does this
Set(
vID,
ThisItem.ID
);
Set(
stPDFName,
ThisItem.Name
);
Set(
ViewPDF,
PDFView.Run(
stSite,
Concatenate(
"/",
ThisItem.'Folder path',
First(
Split(
stPDFName,
"."
)
).Result,
".pdf"
)
)
)
The Document property in the PDF viewer is this
ViewPDF.pdf
The Flow does this

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