ECU, it is said to be best to pull it, but someone did a thread about how he did his easily without yanking it. i would take some perspective (mine.LOL). if it has almost 200K on it, at some point in the not too distant future, chances are something will need to be done to the motor. were it me, unless the leaks are horrible, i would leave them alone. hate to do all that work, and then not long afterwards, pull it all to do some engine freshening. just my thinking.
good advice on the fixin of leaks. if it leaks, manually fix it. no snake oils.
if a cars 5.0 got over 200,000 miles but still running fast, would just a ring bearings and gaskets work! response , ideas ect any one??????