Has anyone put a 2000 intrigue 3.5 in a 1999 intrigue?

Yes, they came that way. But why would you - the 3.8 is a good motor too.

your coolant tank should be on the pass. side inner fender

i have to put freon R-134 into my 99 3.8 L, its in the center rear, (away from headlights). you can tell because there is a black nob hooked up to the silver in color tube. with the do it yourself...

As long as the 1999 has the 3.5L engine, yes.

yes They are all the same on the body parts