The second prototype was also constructed from a donor car, although sources disagree on the chassis number and type. Several older sources mention the donor as a 1960 250 GT SWB, chassis 2053GT. Alternatively, other sources have claimed that a 250 GT Boano (0523GT) or a 1959 250 GT SWB (1791GT) was used as the donor car. This prototype was created entirely by the Ferrari factory's racing department under the oversight of Giotto Bizzarrini, including the bodywork. The original chassis was extensively modified, including relocation of the engine mounts lower and further back in the frame. A competition-specification engine was fitted, including six Weber 38 DCN carburetors. The bodywork seen on the second prototype in period photos was rough, unfinished aluminum. The body's ungainly appearance lead the Ferrari team to nickname it "Il Mostro" (the Monster) and the press to call it "The Anteater." Hammer marks, weld beads and bolted or riveted panels could be seen throughout, evidence of the continual modifications performed during factory testing in 1961. Although the body was crudely formed, it displayed features that would be seen in the production 250 GTO, including the overall profile of a low hood and high rear, triple front air intakes, engine bay cooling slots in the front fenders and plexiglass-covered headlights. The interior was hastily constructed and even more minimal than in the production 250 GTO, with scattered instrumentation and a bare aluminum dashboard.