Vanarama National League North overcame South as Brackley beat Braintree 4-1.
It was a lot more straight forward than many predicted with Brad Quinton's Iron impressive in the league so far this season.
But it's Town who go through and Wilkin said his players getting an early goal really helped settle them down.
"We moved the ball well on the day and scored at good times to make what could have been a very tricky game quite comfortable," the former Wrexham manager said.
"Braintree have been on a good run and are going well in the league and we knew we would have to be on top of our game to get through.
"We started the game with a good tempo and scoring early settled us and allowed us to manage the game.
"I was delighted with how we applied ourselves and we can now look forward to the draw tomorrow."