Armbrister is probably best remembered for his involvement in a controversial play in the 1975 World Series. In the tenth inning of Game Three, with César Gerónimo on base and nobody out, Armbrister collided with Boston Red Sox catcher Carlton Fisk while running out a sacrifice bunt, leading to a wild throw by Fisk and his subsequent failure to get Gerónimo out; home plate umpire Larry Barnett did not make an interference call on Armbrister, a decision which was a source of heated debate after the Reds won the game 6–5.
After baseball, he returned to the Bahamas. He was a craps table croupier at Resorts International’s Paradise Island Casino and worked for at least one other establishment in the gaming business, a staple of the Bahamian tourist economy. As of 2006, he was with the Local Government and Consumer Affairs agency, on Arawak Cay, a popular attraction in the Nassau area. He also served as a consultant to the Ministry of Sports and managed the Bahamian junior national team. In his downtime, Armbrister became a notable local softball player.
In 2008 he was inducted into the Bahamas National Hall of Fame.