Get rid of those Bosch plugs and get yourself some Autolite's. You dont need platinium plugs.
I think the Autolite 605 are the correct stock replacement. Autolite 104's are a few heat ranges colder then stock, but have a good following on clubgp. Plus they're only $1 a plug.
Also, use plenty of Dialectric grease on the plugs/wires/coils
Tim