hi i will be fitting a sub in the boot of my octy in a couple of weeks ,can anyone tell me the best pace to attach the ground wire

cheers

depends where in the boot, As per other thread, seat belt attachmentto bodywork. or possibly in wheel well somewhere, Also and this is what i went for, theres plenty of bolts and wht have you around the rear light in the side compartments, These work well. Just remember to rub the paint layer down to bare metal before attaching it, also try and keep the earth cable as short as possible!

so as long as it makes contact with bare metal on the bodywork and i keep it as short as possible it should be ok