I replaced the plugs on a 2004 caddy cts for my kid
Pita, you have to take off the intake manifold
I had a car — I don’t remember which one — that required the engine to be lifted off its mounts a couple of inches in order to replace the oil filter. It was one of the many $hit boxes that I owned in the early 80s.
2004 Caddy CTS used the same engine as the Caddy Catera of 96-2001
And yes, you do need to take off the manifold to get to the plugs
Wait till you have to do the timing belt, which should be done very 60K or less