Ameriquip now has the old manuals online. Here are some links:
http://www.amerequip.com/assets/docu...30-backhoe.pdf
http://www.amerequip.com/assets/docu...40-backhoe.pdf
http://www.amerequip.com/assets/docu...28-backhoe.pdf

As you can see, just edit the model number in the link if you have a different ARPS backhoe.

Edit: Better yet, here is their library page: http://www.amerequip.com/document-library.html