@ Ddey65: as 1960 model, no GMC forward control bus/coach chassis matches this set forward front axle. See the SP-5000, which has a set back front axle front axle:


This one is most probably based on a modified "cowl + chassis" S-4000 / S-5000 chassis... with a 1960 medium- / heavy-duty Chevrolet grille fixed on the face