On my '99 LX 470 they where toward the back of the block on either side like Dan said. I had no running boards and slightly larger BFG's so I didnt have to jack the truck up. Just slid under behind the front tires with a flashlight and poked around until I found them. It was a reach but they weren't hidden. I used some plastic tubing on the nipple and opened the drain. I don't remember what size the bleeder was. Not much came out from them after I dumped the radiator.