I’ve had the infamous clonk that you can feel/hear intermittently through the steering when stationary/at parking speeds for a while, it only occasionally happened at <30mph over undulating corners and never during spirited driving so let it be until it started happening more often recently.
I tightened the UJ bolt and it still clonked when parking but the steering felt a bit more responsive. A few days later tried turning the steering and feeling the intermediate shaft with my other hand and the knock felt to be coming from the UJ. With the engine off the UJ could rock by hand to recreate the noise. It seemed to either be the UJ or the input shaft on the rack, as they both moved together in sync with the noise.
This morning I removed the bolt and rocking the UJ made a tapping noise against the input shaft, much moreso when the UJ was slid higher up the shaft, so slid the UJ to the bottom of the rack's input shaft (slides easily), installed a fresh nut/bolt and it's much better. I can no longer rock the UJ with my hand and make it clonk and it never clonks when moving. The only time I can get it to clonk now is when stationary, turning left then quickly turning right (vice-versa) and having a feel it's the UJ.
When installing a new nut & bolt, the nut slots into the back of the UJ and has to be held in place with one hand while tightening the bolt bit by bit with the other. Some may have an encased nut on the UJ but a new one is just a nut. A couple of extensions on the ratchet helps to remove/install the bolt with enough clearance of the pedals.
Nut: 7701052817
Bolt: 7703602246
TLDR – Steering clonk @ low speeds improved by removing nut/bolt (13mm) from UJ in drivers footwell, sliding UJ as far down
steering rack input shaft as possible and fitting new nut/bolt.