friend of mine inherited a 1997 Century from his grandfather when he passed away in 2013, it only had 44k miles at the time, it now has 84k miles and runs excellent, despite finding brown sludge in the radiator on the last oil change I did on it. Seems like the intake gaskets that these engines are known for. How difficult of job is it those of you who have done it before? Looked on youtube it doesnt look bad at all and my buddy, who is not mechanically inclined whatsoever, has lately become interested in learning how to change his oil (I showed him how today) and fix things on his car. I figured this would be a good way to learn, I'll do most of the repair, but I'll let him get his hands dirty as well. Currently running Rotella T5 10W30 and a Fram Tough Guard 3387A. Looks clean as new through the fill hole.