that one at bowtie is the usual aftermarket control and knob found on many trucks now, after the originals packed it in - the factory one matched the 5-9 knobs, like this, tough to find nowadays and not repro'd, but the plain black knobs available could be adapted

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 & Rust-a-holics Unanimous parking lot