1 Ron Stygar provided a writeup on how to install chromed Z8 windshield washer nozzles on a Z3. His instructions and all of the needed part numbers are in Parts and Installation. At the time, Ron also sold a kit that included some custom clips that accounted for the slight dimensional differences between the vehicles.
This is the Z3 factory nozzle after I removed it from the hood.
2 This is the underside of the driver side Z8 chrome nozzle showing the "Mix Clip" adding additional retention force. Although not strictly necessary, the custom clips take up the tiny bit of slack due to the Z8 nozzles being just a hair loose in the Z3 hood openings.
3 The passenger side Z8 nozzle in place
4 Underside of the Z3 hood with both Z8 chrome nozzles installed and before reinstalling the hood pad.
5 The final result, classy!