Hi Geoffrey, need a bit more info here - your picture shows the UN1 with Tornado bellhousing / extended fork and clutch release bearing. When they are pushed back hard against the bellhousing you should have a sleeve around the input shaft that the bearing slides back and forth on. There isn't anything else in there apart from your clutch items bolted to your flywheel, and the crank spigot bearing (that the end of your input shaft sits inside)
The other end of your fork sits in the Renault slave cylinder - pic attached....