I didn't really believe it, but it really works!
Don't have any good photos, but indexing works. Indexing is the concept of arranging the spark plugs to face the same direction - usually with the electrode gap facing towards the intake valves, or the exhaust valves. Although I was skeptical, I went ahead and ordered a copper washer kit designed specifically for this purpose, and gave it to my friend Thomas to try out on his engine (R33 GT-R as well), last week. He immediately reported pretty good results - but I remained skeptical.
So, while I prepped two of my alloy wheels for painting (see next post) Thomas indexed the plugs in my engine.
And guess what - just like he said, the engine DOES run better - a bit. A little bit smoother, a little more responsive - at idle, definitely smoother and the exhaust sounds a bit better. And on the road, the engine responds a bit more aggressively - making the car easier to drive on the road.
I posted my results onto the GTR forum, but no one seems to care. It's either the placebo effect for BOTH of us, or too subtle for most people. But any little bit, adds up, and the cumulative effect is well worth it!