Question: How many specials were aired on the series that Buddy Van Horn doubled for Guy Williams on?
Context: Arther Wesley Van Horn (1860-1931) was a prolific architect of Bismarck, North Dakota.  He began as an independent architect in 1883, worked within Van Horn & Loven during 1917-1919, and within Van Horn & Ritterbush Brothers during 1920-1931.  The Bismarck-based firm evolved as Ritterbush Brothers during 1931-1974 and subsequently as Ritterbush Associates. The Dead Pool is a 1988 American action film directed by Buddy Van Horn, written by Steve Sharon, and starring Clint Eastwood as Inspector "Dirty" Harry Callahan.  It is the fifth and final film in the "Dirty Harry" film series, set in San Francisco, California. The Van Horn Mansion was built by Judge James Van Horn in 1823.  It is the site of the Town of Newfane's first town meeting, April 6, 1824.  The name for the Town of Newfane is believed to be chosen by the town Postmaster.  The Mansion includes 16 rooms and five bathrooms.  It is located on Lockport-Olcott Road in Niagara County, New York on Route 78 and is also considered to be haunted.  It is one many National Register of Historic Places in Niagara County. Zorro is an American action-adventure western drama series produced by Walt Disney Productions.  Based on the well-known Zorro character created by Johnston McCulley, the series premiered on October 10, 1957 on ABC.  The final network broadcast was July 2, 1959.  Seventy-eight episodes were produced, and 4 hour-long specials were aired on the Walt Disney anthology series between October 30, 1960 and April 2, 1961. Guy, Sharyn & Clint was a MediaWorks New Zealand brand, composed of personalities Guy Williams, Sharyn Casey and Clint Roberts.  The trio hosted The Edge drive show "The Edge Afternoons with Guy, Sharyn & Clint", Saturday show "The Edge Fat 40 with Guy, Sharyn & Clint", and Four television programme "The Xtra Factor", a follow-up programme of the second New Zealand series of "The X Factor".  The brand was discontinued at the end of 2016, when Guy Williams and Clint Roberts left The Edge.  Their former drive slot was filled by "The Edge Afternoons with Jono, Ben & Sharyn". State Highway 54 or SH 54 is a 55.2 mi highway maintained by the Texas Department of Transportation (TxDOT) that runs from Interstate 10 and U.S. Route 90 in Van Horn north to US 62 and US 180 between Salt Flat and Pine Springs near Guadalupe Mountains National Park.  The route, located in western Culberson County, is largely isolated passing through no cities or towns beyond Van Horn and intersecting no other highways between Van Horn and its northern terminus.  Within Van Horn, the route has intersections with Business Interstate 10-D and Farm to Market Road 2185. Christian Van Horn (born 1978 in Rockville Centre, New York) is an American operatic bass-baritone and has appeared with many of the world's most prestigious opera companies, including San Francisco Opera, The Metropolitan Opera, Lyric Opera of Chicago, Bayerische Staatsoper, Teatro dell'Opera di Roma, Netherlands Opera, Salzburg Festival, Los Angeles Opera, The Grand Théâtre du Genève, and Canadian Opera Company.  His roles include the title role in Le nozze di Figaro, the Four Villains in Les Contes d'Hoffmann, Mephistopheles in Faust, Zaccaria in Nabucco, Escamillo in Carmen, Raimondo in Lucia di Lammermoor, Banquo in Macbeth, Colline in La Bohème, and Claudio in Aggrippina.  Van Horn has also appeared as a concert soloist with the Berlin Philharmonic, Chicago Symphony Orchestra, San Francisco Symphony.  Melbourne Symphony Orchestra, and the Los Angeles Philharmonic among others. Buddy Van Horn (born August 20, 1929) is an American stunt coordinator and film director.  He directed the Clint Eastwood films "Any Which Way You Can" (1980), "The Dead Pool" (1988), and "Pink Cadillac" (1989).  A long-time stunt double for Eastwood, he was credited as the stunt coordinator on Eastwood's films from 1972 to 2011, and as second unit director on "Magnum Force" (1973) and "The Rookie" (1990).  He was sometimes credited as Wayne Van Horn in the 1980s.  He earlier doubled for Guy Williams on Disney's "Zorro", and Gregory Peck.  Van Horn's most prominent onscreen appearance is the role of Marshal Jim Duncan in the Eastwood film "High Plains Drifter" (1973). Any Which Way You Can is a 1980 American action comedy film, starring Clint Eastwood, with Sondra Locke, Geoffrey Lewis, William Smith, and Ruth Gordon in supporting roles.  It was directed by Buddy Van Horn.  The film is the sequel to the 1978 hit comedy "Every Which Way but Loose". The 2002–03 NBA season was the 76ers 54th season in the National Basketball Association, and 40th season in Philadelphia.  During the offseason, the Sixers acquired Keith Van Horn from the New Jersey Nets.  Van Horn was originally drafted by the Sixers as the second pick in the 1997 NBA draft.  The Sixers got off to a fast start winning 15 of their first 19 games, but would then lose 14 of their next 18 games.  The team improved on their last season posting a nine-game winning streak at midseason, finishing second in the Atlantic Division with a 48–34 record, with the #4 seed in the Eastern Conference.  The Sixers defeated the New Orleans Hornets led by Baron Davis in six games in the first round of the playoffs, but they could not go further in the next round as they lost to the Detroit Pistons in six games.  Following the season, Van Horn was traded to the New York Knicks.
Answer: 4 hour-long specials