Most people these day who need to remove the shock towers just pick from among the many Mustang II style front end suspension kits. Using one of these kits completely eliminates the shock towers which allows you to use a big-block or one of the new Mod motors with room to spare.
You'll find many how-to articles on the net with plenty of pics to help you along.
Seriously, if you are having trouble getting to the spark plugs, just invest in a set of Motorcraft double-platinum plugs. Last 100,000 miles, and lots easier and cheaper than converting your engine compartment.
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