That should be the same old Cummins Big Cam 855 Ci. engine used in just about all Italeri American truck kits. It should be painted Cummins beige. The colors changed when cummins upgraded that engine and changed the designation to N-14. Black for N-14 and black with red rocker covers for N-14 Plus. Their was a long post about 4 months ago listing most engines and their colors.