2000 XLT 4DR 2WD. 4.0L SOHC JOB 1 VIN E. 5-Speed Automatic O/D 5R55E. 158,000 miles.
I replaced the rear hydraulic tensioner (Ford OEM hydraulic tensioner 7U3Z-6K254-A installed August 2022 at 149,000 miles), which was working properly, with a manual tensioner (Alpha Rider Cam Timing Chain Tensioner Manual W/Gasket For Polaris Ranger 1000 RZR 570 XP 900 ACE Stainless Steel; Amazon).
Thanks to everyone's advice and tips, the job went smoothly.
I did 3 "passes" of tightening the tensioner pin: (1) rotating the engine clockwise by hand, (2) rotating the engine with the starter while the fuel pump relay was disconnected, (3) running the engine.
I ended up with about 2 threads of the tensioner pin showing above the lock nut (not zero threads as shown in C420sailor's picture above).
On first startup (warm engine), it started and ran quieter. However, the real test will be the first startup this morning (cold engine). I'll report back how it goes. Also, soon, I'll be replacing the front hydraulic tensioner with an Alpha Rider manual tensioner.