actually there's 4, + the very front and very back - the middle 2 are thinner than the other 2, as they go in the area where the frame kicks up - and I hope you're not welding them to the frame of the truck eek they bolt to the bed wood and box, then the whole unit bolts to the frame

Bill

Moved over to the Passing Lane

"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