The battery case works perfectly however it is much larger than the original and locating it is a problem. I had to adhere it to a large chip and I hope that doesn't cause a problem in time. the computer is a mac Performa tower. Other models may allow more room. I don't believe there is an alternative to this setup so I still recommend it.
Faulty manufacture and non-existent quality control. Black wire was not crimped in the 4-pin connector, I had to cut the wires and install my own connector and wires to the pack.