Can't say I'm thrilled to hear that. The wife's 5.3 Envoy has 104k on it and I've been procrastinating.
I did plugs at 200k and it's due again with 270k on my 5.3 rainier but honestly the rear main seal is leaking so bad and the oil pressure fluctuates because the pickup o-ring must be cracked that it cavitates sometimes, so I am beyond caring about the little things.
But yeah the job sucks. I think mine had OE plugs (or at least VERY old ones) because I snapped 3 or 4 boots off the wire sets when I did plugs. I'd order a new set of wires too when you do them.