I'm getting ready to transplant a "high output" 3.5L from 99 LHS into my 97.
I've got the engine and trans from the 99 with both ECM's.

Acouple questions that hopefully someone with more experience on these cars could answer.

1. What differences are there between the "HO" and regular 3.5L engines?
2. Were there any differences in these model years?
3. Which would be easier to perform? Complete engine with trans swap or just engine?

I'm guessing that I'll swap the engine and use their ECM.

Thank you.