The helm's manual recommends NGK platinum plugs for the vtec engines and just the coppers for the non-vtec... but they can be used if u want. So since you have a 99... I would go to auto zone or wherever and get the platinums... they'll last longer and there's no gapping them.

Make sure your engine is cold when you change them... and put a little anti-seize on them before you put them in... then just make them nice and snug... don't turn too hard... that head is aluminum ya know.