Proper: "you guys are (crazy)" "ustedes estan (locos)".
"Guys" is "Muchachos". You could say "they", which is "ellos". You could also say "ustedes", which means "you guys", or sometimes, "ya'll".
Muchacho
Chicos guapos
OS echo de menos
Cuatro hombres guapos
Estas conectado(for guys), conectada(for girls) en facebook?
It means, "All you guys say it again."
porqué haga el tramposo de los individuos
Translation: ¡Ustedes están hablando demasiado rápido!
Te amo chicos, or amigos.
ustedes significan todo para mi ustedes son mi mundo
They're lots of ways to say that. You could say "Los amo/quiero (a Uds.)" or "(Uds.) me caen muy bien (a mi)". I would say, personally, "Los quiero mucho". They'll understand that.