I need to find out where I can purchase a Battery Cable Engine Harness for a 1997 Infiniti J30t or if I can just bypass this thing...mine is loose and unless I tape it down and make sure its connected the car will not start. I have tried to find the part in all of the automotive stores in my hometown and several salvage yards to no avail. Any ideas?

It's really tough to deduce your problem based on your vague post. If I am understanding correctly you have an easy fix:

You can buy shims that go over the posts of your battery, which makes a larger post for the terminal to secure to.