I found a method to merge all 8 individual scanned pdf's into one pdf, using preview, on my Mac.
1. Put the individual 8 pdf pages into one file folder.
2. Open the first pdf (page 1)
3. Activate the "thumbnails" on the preview.
4. Highlight all the other pdfs (page 2-8)
5. Drag and drop those 7 pdfs into the thumbnail portion.
6. Now save the preview; if you want, rename it when you save it.
7. Open the merged file, and note all pdfs are in one pdf document, but has 8 pages. You can also rotate those pages individually.
