Munro displayed his delight with an extended flourish of his whip in the last 50m driving Independence Day.
He had the 4yr-old trotter in front after 400m from an unruly draw and won by two and a-quarter lengths.
Munro began driving in August and he was having his 25th drive.
He is employed by Weedons trainer Jamie Gameson, who prepares Independence Day.
Munro has been with Gameson for 18 months.
He was familiar with stable routine, having assisted his father, Templeton trainer Neil Munro, from early childhood.
Independence Day, who was having his ninth start, will now be spelled, bypassing the Cromwell meeting on Thursday.
• Colin McPherson had his first win as a trainer yesterday after holding a licence for 14 years.
He won with Felix Hanover, whom he races with his wife, Sandra.
"I have had a few horses but have either sold them or passed them to other trainers," McPherson said.
He earlier assisted his father, Ian, who prepared the useful winner, Mister Smart, at Croydon.
Colin bought Felix Hanover at the NZ Premier Yearling Sale when the son of Badlands Hanover and Glimmering was offered by Jim and Susan Wakefield, of Christchurch.
Felix Hanover is a half-brother to Beau Rivage, the winner of seven races when trained by Cran Dalgety.
Beau Rivage ran 1.49.4 in the United States.
Glimmering has left one other foal, the winner Beau Shiraz.
• Another Homer was rewarded for consistency when he won the Roxburgh Cup decisively yesterday.
He led over the last 1800m and won by two and a-half lengths.
Another Homer had finished a close second in the Reefton Cup and third in the Westport Cup in the past nine days.
He is trained at Leithfield Beach by Robbie Holmes for Waipara breeder Graham Pearson.
Another Homer is an acceptor for the Cromwell Cup on Thursday.
Holmes also has Biella Star in that race.
Biella Star finished third to Cullen's Creek and Pretty Dollybird in the Central Otago Cup on Saturday.
Holmes retained Peter Davis to drive Another Homer yesterday after the latter had driven the horse on the West Coast.
Another Homer travelled to Roxburgh with trainer Margot Nyhan, partner of Davis.
Nyhan and Davis teamed to win yesterday with Life Goes On, a 9yr-old.
Gary Shand was fined $200 for excessive use of the whip on Mighty Memories, who finished third in race 9.
