Question: In what city were the Track Marshall brand of earthmoving equipment manufactured?

Context paragraphs:
BelAZ: BelAZ (Russian: "Белорусский автомобильный завод" or "БелАЗ" , Belarusian: "Беларускі аўтамабільны завод" , Belarusian Automobile Plant, Romanized: "Belaruski autamabilny zavod" or ("BelAZ") is a Belarusian manufacturer of haulage and earthmoving equipment based in Zhodzina.  The factory opened its door in 1948 and has produced over 120,000 vehicles for use in the Soviet Union.

Fiatallis: Fiat-Allis (1974 to 1985), later renamed Fiatallis (1985 to early 1990s), was a brand of heavy equipment (also called construction equipment, earthmoving equipment, or engineering vehicles), such as loaders, bulldozers, backhoes, scrapers, and graders.  It began in 1974, when Allis-Chalmers's construction equipment business was reorganized into a joint venture with Fiat SpA, which bought a 65% majority stake at the outset.

John Fowler &amp; Co.: John Fowler & Co Engineers of Leathley Road, Hunslet, Leeds, West Yorkshire, England produced traction engines and ploughing implements and equipment, as well as railway equipment.  Fowler also produced the Track Marshall tractor which was a tracked version of the Field Marshall.  British Railways Engineering Department locomotives ED1 to ED7 were built by Fowler

Louden Whirl-Around: The Louden Whirl-Around is a historic object located in Fairfield, Iowa, United States.  It is a type of a playground merry-go-round manufactured by the Louden Machinery Company.  It was built about 1930 on the grounds of the Fairfield Country Club.  The octagon-shaped apparatus is composed of steel pipe, malleable iron couplings, and wood.  It is located south of the swimming pool behind the clubhouse.  Louden had to begin a line of playground equipment in order to acquire patent rights that it needed to develop its line of overhead material handling systems.  They acquired the J.C. Porter Company of Ottawa, Illinois, which manufactured the playground equipment and held those rights.  The playground apparatus exemplifies the company's growth in the 1920s.  Most of the schools in Fairfield had playground equipment manufactured by Louden.  The object was listed on the National Register of Historic Places in 1999.

Field Marshall: Field-Marshall is a brand of farm tractor which was manufactured by Marshall, Sons & Co. of Gainsborough, Lincolnshire in the United Kingdom.

Blue Force Gear: Blue Force Gear, Inc. is a United States manufacturer of body armor, Modular Lightweight Load-carrying Equipment (MOLLE) gear, firearm slings, and other tactical equipment that was established in Pooler, Georgia during January 2004.  They design and manufacture equipment for law enforcement, U.S. Armed Forces (and NATO Forces), and Sport Shooters.  Select equipment manufactured contains a National Stock Number (NSN) and a National Item Identification Number (NIIN) for supplying armed forces.  Its name, Blue Force Gear, is derived from military symbology dating back to World War I: blue being for Allied forces and red for enemy forces.

Renwick Generating Plant: Renwick Generating Plant, also known as the Municipal Steam Light Plant, is a historical industrial facility located in Renwick, Iowa, United States.  G.L. Long was an engineer who was contracted in 1914 to design a steam-powered electrical light plant.  It first distributed energy on March 14, 1915, at 6:00 p.m.  The steam engines were replaced by a 75-horsepower, two-cylinder, semi-diesel engine and generating equipment manufactured by Fairbanks-Morse in 1922.  A 125-horsepower diesel engine manufactured by Worthington Pump and Machinery Corporation was added in 1936.  At that time the plant started to supply power to a newly formed rural electric cooperative that was funded by the Rural Electrification Act of 1936.  A Faribanks-Morse 300-horsepower, four-cylinder diesel was added in 1939, and the 75-horsepower and 40-horsepower engines were replaced in 1942 by another 300-horsepower diesel.  An addition was added onto the north side of the building the same year.  It housed the local fire department and city hall.  The facility was listed as a historic district on the National Register of Historic Places in 1995.

RCA Spectra 70: The RCA Spectra 70 was a line of electronic data processing (EDP) equipment manufactured by the Radio Corporation of America’s computer division beginning in April 1965.  The Spectra 70 line included several CPU models, various configurations of core memory, mass-storage devices, terminal equipment, and a variety of specialized interface equipment.

Track Marshall: Track Marshall was a brand of earthmoving equipment who were active during WWII building tanks. Later, they produced a range of crawler tractors, based on the wheeled tractor "Field Marshall" brand.  In 1956 the first Track Marshall bulldozer model was introduced and later the Challenger 3 followed by the Challenger 33, the "TM55" and also the successful six-cylinder "TM70" (probably equivalent to a Caterpillar D5).  They also built the TM 955 track loader (a "drott") and also a range of rubber tracked bulldozers.  The company was in business for some 50 years, eventually closing in 1990 after new machines replaced older technology.

R. G. LeTourneau: Robert Gilmour LeTourneau (November 30, 1888 – June 1, 1969), was born in Richford, Vermont, and was a prolific inventor of earthmoving machinery.  His factories supplied LeTourneau machines which represented nearly 70 percent of the earthmoving equipment and engineering vehicles used by the Allied forces during World War II, and more than half of the 1,500 mile Alcan Highway in Canada was built with LeTourneau equipment.  Over the course of his life he secured nearly 300 patents relating to earthmoving equipment, manufacturing processes and machine tools.

Supporting paragraphs: Track Marshall Field Marshall
Answer: Gainsborough, Lincolnshire