Spark plugs covered in oil - how screwed am I?

How Much oil do you use per 1000 miles?
Blue smoke on startup?
Pull valve cover and look at your valve seals. V8’s have neoprene umbrellas, not sure about/6’s. They get old they harden and bust up to pieces from heat cycling.

Compression test will tell you if you have a real problem, followed by a leak down test will give you a good idea what the problem is.