I've almost got 6000 miles on my GT300i and am looking at the needed maintenance. I noticed in the service manual that they recommend replacing the spark plug at this point. First of all, is that really necessary -- seems like a spark plug should last longer than that (at least the ones in my car don't need to be changed until 100K miles). But if it does really need to be changed, does anyone have a suggestion as what to replace it with (especially if that replacement would last longer than the original)?
Thanks for any advice.