This is the one I used. (All Pokemon can be obtained before battling Chuck)
Victreebel: Cut, Sleep Powder, Razor Leaf, Sludge Bomb
Poliwrath: Surf, Submission, Hypnosis, Body Slam
Golem/Graveler: Explosion, Earthquake, Rock Smash, Strength
Arcanine: Extremespeed, Flamethrower, Rest, Sleep Talk
Xatu: Fly, Psychic, Night Shade, Flash
Ampharos: Thunder/Thunderpunch (Your Choice), Iron Tail, Toxic, Light Screen
If you like the starters replace Victreebel with 
Meganium : Body Slam, Reflect, Synthesis, Razor Leaf
Victreebel will help you catch Pokemon and take care of water and ground types. Meganium will be able to set up reflect to raise your tems defense and take care of water and ground types, decent chance to paralyze with body slam. Poliwrath is all out attacker and can also put Pokemon to sleep. Golem will earthquake through the oposition and then explode when it is at low hp. Arcanine uses the classic rest sleep talk strategy with STAB flamethrower. Xatu is your flyer. Ampharos can set up light screen and toxic if Meganium sets up reflect it can mini-stall.
Store desired HM slaves in the box until you need them.