i just did this about a month ago actually, and you need to be at a VERY high level. i was around level 84 i believe, and i still fainted twice. but for movesets, you're best bet would be to go with:
flamethrower (you'll need the PP, fire blast even with a PP max isn't enough) use it on jynx, all of agatha, pidgeot, and exeggutor)
brick break- maybe not the most powerful but type coverage is almost exactly the same as steel wing/metal claw/iron tail, and it's 100% accurate; use it on everyone of lorelei's pokemon save jynx, onix, rhydon, and either this or dragon claw on aerodactyl
dragon claw- i wish i'd had this attack... use it on lance's entire team, they'll all die pretty quickly. you'll probably be lucky in that they'll use outrage which will limit their ability heal up
wing attack- bruno's fighters, alakazam, maybe blastoise, and arcanine (dragon claw is an option for him too, especially after an intimidate)
make sure you have plenty of revives and hyper potions and that you're at a very high level to stand a chance against blastoise. have at least 4 other pokemon with you to use at bait while you heal up zard.
-kb