...

1. Power on replacement-switch in lab-rack or similar with console access
2. Connect via console and do "zerotouch cancel" if needed
3. Copy configuration from old switch from NMS WebUI Devices → Click on device → Actions menu → Copy generated config
4. Paste config to replacement switch, if it already has some previous config do configure session → rollback clean-config before pasting new config (paste with delay between lines or paste in chunks if configuration is not applied correctly)
5. wr config
6. Physically replace switch
7. Sync device from NMS WebUI
8. Update facts from NMS WebUI, update serial in NI etc