Can you share what (if anything) you had to do to that engine to put it in your LR3? Is it a one-for-one swap? Why did you pick a 2008 Ford Ranger (vs. a 2005 Ford Explorer or another vehicle)?

(I need to decide if I replace the engine in m,y '06 LR3 or if I junk it.... timing chain guides went at 190K miles)

 

Click the link I posted above for a pretty thorough explanation of what he went through to replace his engine with a Ford Ranger / Explorer 4.0L v6. It's all there. You just need to read the thread for your answers.
I'd just replace the chains and guides if the engine otherwise runs fine. Bummer is you need to pull the engine to do it properly. I did mine at 153k.