"This is the first time we've had so many grand finalists in one room," said NZ Young Farmers chief executive Terry Copeland.
Guests entered the venue through a corridor lined with contest memorabilia, including trophies and winners' cloaks.
"It's been great catching up with people who were involved with the contest at the same time I was," Williams said.
Williams was 27 years old when he took out the national final in 1973. Back then the contest was still a radio quiz.
"There were no practical elements like there are today," said the retired sheep and beef farmer.
"I think it's much better having a mix of theory and practical challenges.
"In 1973 there were only four grand finalists — two from the North Island and two from the South Island. It was quite different to what it is now," he said.
The inaugural television broadcast was in 1981.
"We were all pretty green about what was required for television," Copeland said.
"We were extremely dressed up and serious. Today the contest is more entertaining and has a bit more audience appeal."
Copeland, who now owns four small dairy farms with his wife Cynthia, still recalls the modules finalists had to tackle.
"Horticulture was just coming into its own in the 80s, so we had to plant and prune a few trees," he said.
"We also had to hang gates, fix a water pump, repair the chain on a motorbike and deal with a tractor that had run out of diesel."
The contest marked another major milestone in 1981.
North Otago sheep and cropping farmer and part-time farm consultant Denise Brown (now Clemens) became the first female grand finalist.
"I really admire the women who make it through now because the contest has a much larger practical component," said Denise.
"I don't think it will be long until we have a female grand champion. Women can do anything."
Ashburton arable farmer Tim Porter won in dramatic fashion in 2002 on his second attempt at the grand final.
"I ended up in a dead heat and they had to do a countback which took five to 10 minutes," Tim recalls.
"It was a nervous wait for my family, but I was just happy to be finished."
Tim always had a desire to follow in the footsteps of Catto twins Warwick and Grant — who both took out the title.
"I used to shear with Grant. I remember he'd sit there studying the Lincoln Farm Technical Manual during smoko breaks," he said.
"It's been a goal of mine since I was a teenager to the win the FMG Young Farmer of the Year contest."
The winner's prize pool has varied over the years, but often included farm machinery and overseas travel.
"My prize included a ute, a motorbike and an Air New Zealand travel package," said Tim.
"I won a 21-day trip around Hawaii in the United States and a new tractor," added Geoff.
"But most importantly I won the esteem of winning the Young Farmer of the Year which has been great throughout my whole life."
