Jay Mercedes use chain on many Engines both Diesel and gas models
with a hydraulic tensioner from the Engine oil maby you can use some
ideas from there
The V8 from the 80s is a sohc and use a chain.
I have one but have never touched the Engine
it just runs and run.So i dont know how they
made the tensioner.
The later V8 up till late 90s is a dohc but is said to be the same Engine
exept the heads .
I have one of those to but never touched that one either
It have Electronic variable cam timing....If that give you some ideas