Bill was just 17 when he stepped through the doors of Stevenson & Taylor as an apprentice diesel mechanic.
He worked for Stevenson & Taylor founders Bill Stevenson and Peter Taylor, with Bill Stevenson as his mentor.
"Bill was a great guy, and shareholder John Fergusson was also a very good mentor and taught me a lot," he said.
"I did my time and became a registered A-grade diesel engineer. It's been a good journey - not many guys stay with the same firm their entire working life."
When Bill started, farmers were still breaking in country around Porangahau, Wanstead and Wimbledon, root raking, discing and burning off trees.
"It was too dangerous for wheeled tractors so it was all crawlers. It was heavy, hard work and the machines broke down all the time. We had to service them in the field - there were no transporters.
"The contractors were tough and hard workers and they earned their money, I can tell you. It was dusty, the cabs were open and their backs didn't last - there were no springs. I have a lot of respect for those early guys. Farmers too, they went and broke the land in themselves. People forget that."
In the '70s, Bill became financially involved with the business. Around the same time, 4WD tractors started to come in.
"They got over the country and did a lot of agricultural work. Contractors started buying them. The technology around engines, transmissions and hydraulics changed massively," Bill said.
Technology leaped forward into the '90s and then jumped again. From '97 onwards computers controlled transmission, then engines in the 2000s. Along with tractor sales and servicing the engineering side of the business was also going ahead.
"We designed and built equipment as people needed it; buck rakes, squash harvesters ... we were the first in New Zealand to build hydraulic log splitters. I'd built one for myself and decided we might as well make some for clients. We're still building them."
A key message drummed into Bill by his mentors was that good staff was one of the most important things.
"You have to be fair and reasonable to staff and customers. No staff means no company. And it's important to have a range of ages too, older staff with knowledge that isn't on a computer screen. When you get an older vehicle in, someone has to know how to fix it.
"Stevies sold machines to farms as far back as the 1950s ... and we're still working on them."
One of the highlights for Bill was selling the old building and designing and building afresh in Takapau Rd.
"We haggled for two years to sell the old building, then leased it back while we built the new one and with the main road exposure and bigger workshops the company took another huge leap forwards."
Now, it's Robby Smith at the helm and Bill says Robby's story is similar to his own.
"Robby came straight to us from school and has been with the company for 20 years. He always told me he wanted my job and I was right behind him - he deserves to have it."
Robby in turn says Bill has pushed him to do well.
"Bill might have been the GM but he was hands-on. When I started, he'd still put on overalls and help us out. He taught me his values and his can-do attitude. It seems weird not to have him in the office but I can still ring him and he's happy to help."
Retirement to Bill is a chance to spend time with his family, who he feels missed out a bit when he was working long hours and on call. He has grandchildren to enjoy, a new house with unfinished projects to get stuck into, and two much-loved classic Jaguar cars that have been "mothballed" until he had time for them.
But he'll still be calling in to Stevies to catch up from time to time ...
"I'm still a diesel engineer at heart."
