I agree with Unknown_K. If you are installing surface mount tantalums, the line on them means positive.

The IIci does NOT require a working battery to turn on.

I would recommend pressing on your new capacitors as you press the power button, particularly the ones nearest the power supply connector. Sometimes they look soldered but actually are not making contact. You may need to remove the logic board from the IIci and carefully attach the power supply to it in order to be able to touch the caps as you press the power button.