The behemoth NC 150 as we know it now humbly appeared as new primary routing in 1929, running only from NC 10-80 (now just Innis St) west to US 21/NC 26 (now NC 115) Mooresville. NC 150 may have duplexed with NC 10-80 south on innis to US 170/NC 15 (now US 29).

NC 150 original route 1930 Official

In 1931, NC 150 was extended west as new routing to Lincolnton, then replaced NC 206 southwest to end at US 74/NC 20 Shelby.
In 1940, NC 150 was expanded in both directions:
Southwest replacing NC 184 to Boiling Springs, then south as new primary routing to the South Carolina line.

NC 184 west of Shelby 1938 Official

NC 150 replaces NC 184 1940 Official

Northeast replacing the lengthy NC 703 through Winston-Salem and Kernersville and out to US 158.

NC 703 north of Yadkin River 1936 Official

NC 150 replaces NC 703 1941 Official

Also in 1940, NC 150 was removed from Lincolnton St, Fulton St and Innis St in Salisbury and instead placed on Mooresville Rd directly to US 29 Main St.

NC 150 to central Salisbury 1940 Official

NC 150 veers SE to US 29 1940 Official

In 1941, NC 150 was removed from Old Salisbury Rd between the Yadkin River and where it left US 29-52-70 and was placed on its current routing through this area.
Between 1950-53, NC 150 was rerouted in Mooresville onto new routing around the north side to US 21 (now NC 115), then south with NC 115 a bit, then used Statesville Ave to cut southeast back to Main St. The McLand St/Main St route through central Mooresville became NC 150-A (now NC 152).
Also between 1950-53, NC 150 was rerouted in Winston-Salem to leave Acadia Ave at Broad, then used Broad south to Sprague, then used Sprague east all the way past US 311's southeast exit from the area. This left behind: unnumbered Acadia Ave; US 52/NC 8 Main St; unnumbered Waughtown Rd east to NC 109; US 311 on Waughtown Rd
About 1953, NC 150 was rerouted on its US 220 duplex when US 220 was rebuilt to the east of Summerfield.

NC 150 in Summerfield 1949 Guilford County

NC 150 on new US 220 routing 1953 Guilford County

Around 1955, NC 150 was removed from central Mooresville altogether, with the rest of Main St renumbered as NC 152.

NC 150 through Mooresville 1949 Iredell County

NC 150 partial Mooresville Bypass 1953 Iredell County

NC 150 complete Mooresville Bypass 1957 Iredell County

Around 1956, NC 150 was rerouted to the south away from central Lincolnton. The old route became NC 150-A (plus NC 27).

NC 150 through Lincolnton 1953 Lincoln County

NC 150 bypasses Lincolnton 1957 Lincoln County

In 1956 or 1957, NC 150 was placed on Peters Creek Pkwy below Acadia (now called Salisbury Ridge Rd), leaving behind today's Old Salisbury Rd.
In 1961, NC 150 was removed from Acadia, Broad and Sprague west of Main St and placed on the new Corporation Pkwy and duplexed with US 52/NC 8 Main St north to Sprague.
Between 1958-62, NC 150 was placed on one-way splits in Shelby with its NC 18 duplex, using Graham St and S. Washington St NB and Lafayette St SB. Then it was placed on one-way splits with its US 74A duplex using Warren St EB and Marion St WB. County maps are vague...the 74A splits could have come much earlier, back to 1949.
Between 1963-68 it appears NC 150 was returned to single routing south of US 74 Bus in Shelby, using Washington and Graham Sts.
Between 1991-93, Corporation Pkwy was reconfigured and NC 150 was moved onto Silas Creek Pkwy east of Peters Creek Pkwy

NC 150 initial Winston-Salem route 1949 Forsyth County

NC 150 moved to Broad and Sprague 1953 Forsyth County

NC 150 moved to Peters Creek Pkwy 1957 Forsyth County

In 1994 or 1995, NC 150 was removed from the Silas Creek Pkwy and Sprague Sts in Winston Salem plus Main St in Kernersville, and instead replaced SR 3013 on the Peters Creek Pkwy (a road dating back to the 60s) up to I-40 Bus, then followed that east to NC 66, then northwest around Kernersville to meet up with traditional NC 150 leaving Kernersville to the northeast.

NC 150 placed on Corporation pkwy 1962 Forsyth County

NC 150 moved to Silas Creek Pkwy 1993 Official

NC 150 moved to I-40 Bus 1999 Official

NC 150 through Kernersville 1993 Official

NC 150 bypasses Kernersville 1999 Official

Also in 1994 or 1995, NC 150 was placed on its current routing around the east side of Shelby as new construction. This left behind its duplexes with NC 18 and US 74 Business.

NC 18/150 placed on one-way splits 1962 Cleveland County

NC 150 back to two-way traffic with NC 18 1968 Cleveland County

NC 150 bypasses central Shelby 1999 Official

In Jan 2008 (NCDOT), NC 150 was placed on a new bypass around the north of Crouse in Lincoln County.
About 2020, NC 150 was placed on a newer bypass east of Kernersville using more US 421 plus the newly constructed Macy Grove Rd. The old route remains NC 66 and N. Main St