Thank you Ian, that sounds very probable as there definitely are no shims. Only a mm or two to work with but that may solve it.
I assumed the rattle from the finder area was due to damage in shipping. Camera was thrown in a simple cardboard box with two air-pillow sheets, not wrapped or secured in any way. Tumbled around from one end of U.S.A. to the other. When the package arrived I was certain I would open only to find a very complicated puzzle of camera bits. Much to my pleasure I was mistaken.
Yashica made one heck of a sturdy camera!