Cleaning an spark plugs

Chrysler has a real good degreaser that looks like thick green antifreeze. GM probably has a similar product. It comes in 5 gallon pails. The product MUST be sprayed or misted onto the engine from a spray bottle. It won't do anything if it is just poured on. Let it sit on a warm engine for 15 minutes, then pressure-wash it off. I've never found a more effective product.

They have a different product in a spray can but it's only meant for small areas.

Sorry that I don't know what's involved with the spark plugs but chances are you'll be removing a lot of stuff to get to them. If you can't get them free with a hand ratchet, warm the engine first then spray the plugs with compressed air to cool them a little but mainly to remove any dirt that might fall into the cylinders.

Caradiodoc