http://www.danroy.com/truck/master.html I have seen a 1954 tow truck with a 1954 Jobmaster 261 engine that has the yellow color. Even though the owner has had the truck for almost 30 years, he does not know if it had been rebuilt/repainted. The link above shows yellow 261s for some years after 1954.
I have a 1960 261 that was green.
Tim
