The Eagles play their football four steps lower on the football pyramid but overcame the odds to become the first club in four years to prevent the Lions reaching the Valley Parade showpiece.
Guiseley had won the trophy for two successive years and only missed out on a hat-trick in extra time last season.
That was to FC Halifax Town, who also beat them in the Conference North play-off semi-finals and then gained promotion to the Premier tier. That puts the achievement of Duxbury’s spirited squad into context.
“It was a fantastic result for us – but no matter what team I put out, I expect a result because we haven’t just got one direction,” said the Eagles boss.
“We have three or four game plans but our first beat Guiseley the other night. I had another ready to implement but there was no need to change the system because we were doing so well.
“It was a tough game but we caught them cold. They settled down after that and we had to battle. It was a struggle at times but apart from two 20-minute spells, I thought we were on the front foot.
“I’m not biased towards my side but we hit the woodwork a couple of times, so it could have been even better.
“I’ve played against Mark (Bower) but I don’t know him all that well – but he and his assistant were very good; very respectful to us and our club.”
Duxbury feels it is too soon to be looking forward to the final against Guiseley’s fellow Conference North outfit Harrogate Town.
“I’m not thinking about that because I’m looking at getting Eccleshill promoted,” he said.
“I know I’ve got 72 Americans (from the RIASA academy) who all want to play at Valley Parade and they are all stepping it up in training, which is good for me as manager looking at pushing for a top-two finish.”