I don't think you'll get very far without a Mouse and Hard Drive.
You could build and test that it powers to the early boot screens and maybe boot a workbench floppy but you won't be able to run any PowerUP apps without a full setup.
Unless you boot OS4 from Floppy & CD, that would prove the PPC is working.
You can move the mouse pointer in Workbench with the Cursor Keys if you hold the Right Amiga Key an I think the ATL Keys are the Mouse Clicks.
Where abouts in the world are you?
Steve.