Packard does not build many cars like the Packard Twelve: a Coachbuilt to owner's preference / 2-door coupé / 2/4-door Convertible (car) / convertible / 4-door Sedan (automobile) / sedan with 424.1 CID V12 engine, made in small numbers.
The background
The Packard Twelve was a range of V12-engined luxury automobiles built by the Packard Motor Car Company in Detroit, Michigan. The car was built from model year 1916 until 1923, then it returned 1933 until 1939. As a sign of changing times, the majority of second generation Packard Twelves received standard bodywork, with custom bodywork gradually losing favor. Many of the custom cars were actually only "semi-customs", with Dietrich assembling Packard-made bodies with special touches.
The engineering
Under the skin sits 424.1 CID V12 engine; other versions carried different engines, listed in the specification table below. The layout matters: a front engine drives the rear wheels, the classic proportion — long bonnet, cabin set back — that most people picture when they picture a sports saloon or a grand tourer. The wheelbase is 125 - (1916-1923) / 127+3/8 in (1938) / 132+1/2 in (1935-1937) / 134+3/8 in (1938-1939) / 135 in (1934) / 139+1/4 in (1935-1937) 139+3/8 in (1938-1939) / 142 in (1933-1934) / 144+1. These are manufacturer figures carried by Wikipedia and Wikidata, not road-test measurements.
Where it sits
Where it sits in Packard's history is not in doubt: the Packard Six came before it; the Packard Custom Super Eight followed it; it was built at Packard Automotive Plant, Detroit, Michigan, United States. Its Packard stablemates include the Packard 160 and the Packard 180.