Charging the Battery on a 92 GP

I've been having a few problems lately lol. Anyways me being dumb i accidently left my interior lights on all night so when i went to go start it..it wouldnt start. The battery couldnt be completely dead cause the lights were still on. Anyways my parents have this battery charger so i went to go put it on but the battery is hidden undead the windshield fluid jug thinger lol. I found the postive one, they have it up above, but I couldn't find the negitive one. I looked at boosting the car in the owners manuel and it just had it cliped to this big piece of metal under the hood which i found, but will it work having the negitive clipped to that when tryin to charge the battery?

nevermind .. my nabiour(sp?) helped me out