I have a 998 c si and want to install a power cord from battery to the unit. I read in humminbird instructions you should use 18 GA. stranded wire. Humminbird Greg recommmended 14 Ga. stranded wire. I would like to use 18 or 16 or 14 ga. stranded twisted pair with a shield for good measure. Does anyone know where I would find this? I think it would be same type wire used for speakers and/or microphones. By the way Lowe's and home depot do not carry it.