If you're willing to clip the wires to the Mobo connector off your IIci PSU inside the case at about the halfway point you're all set. Using that connector/& wire stubs, you can easily adapt just about ANY ATX or AT PSU . . .

. . . and it'll fit into your IIci. :approve:

You can even restore the IIci PSU to its current config at a later date if you'd wish to do so.

Workable PSUs can be found curbside or for a few bucks inside a junker at a thrift store.