Go with the standard heat range Motorcraft plugs and I believe the gap is @ .045" to .048", anything else is really a waste of money. Anyone that starts babbling about their "magic" spark plug doesn't know what they are talking about. Silly claims about "new and improved" electrode configurations are a testament to peoples gullibility. There is absolutely no independent track or dyno data to back up these ridiculous claims. In fact, the actual data disproves the "magic" plug ad campaigns. NO PLUG can increase horsepower or performance versus a fresh set of "standard" plugs...
NGK plugs are very easy to read and they make a good quality performance plug..
Motorcraft (and autolite) make a very good plug as well. I would not hesitate to use either, but I would personally go with the NGK's if I had more performance mods planned.
Platinum and Iridium primarily give longevity over conventional copper, however the copper plugs transfer more spark energy. Save the platinums for the boring daily driver fuel injected car and run the coppers on the car you'll be wrenching on regularly...its part of the fun