drivers side just back of middle, should be an obvious boss on the block with a hole the size of the tube - if it has original rams horn manifolds the tube will nestle between 2 ridges just behind the Y outlet
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics