Yep the k123 single bunk not aerodyne. The orange one with Interstate motor freight on the doors. K100 is the basic series name for cabover Kw's the additional numbers like 23 identify various components. Yes the torsion bar is perfect for that truck as I said that kit originally came with it when first issued. That version is very rare since most of that kit came after the change to the hendrickson suspension. The torsion bar was very common on that truck in real life AMT's K123 is a 1971,1972 model