If RN1 RN2 and RN3 are in place, you should not do anything.
http://amiga.resource.cx/photos/phot...res=hi&lang=en
Please remember to terminate your external SCSI chain.
This is actually an interesting dilemma.. Most Amiga SCSI controllers are set up to only have an internal SCSI chain or an external one. but not both at the same time.