they look like gas tank straps, depending on where the tank mounts ... the pan doesn't look like an engine side cover, but maybe some kind of belly pan under the engine? you need to start searching out pictures of 29-32 trucks and sleuth it out - see this guys photobucket pics and maybe mail him for some consult

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