"The boys did well but it's only half the job done as we've got the second leg to come and that will be a real tough game I'm sure," Heighway told the official website.
"We could actually have scored seven goals tonight but for the City goalkeeper.
"We started well and got the opening goal from Robbie Threlfall. We thought Robbie would be a threat from set pieces so it gave us a good start. Charlie Barnett gives us great deliveries from set pieces. It's easy to look at people like Beckham and Steven Gerrard and say to Charlie they only got as good as they are through hours and hours of practice. That's the incentive for Charlie and the more he practices the better he gets and he's only 17.
"We scored an excellent second goal and Ryan Flynn passed the ball into the net and showed good composure.
"At 2-0 our goalkeeper David Roberts made a fantastic save and sometimes you need that at vital moments.
"I must mention our captain Stephen Darby who was fantastic again at right back. He is a young boy who is slight and a bit light weight but we just couldn't imagine playing without him.
"It was nice to get the third goal and Miki Roque showed a good attitude when he came off the bench. That's what good players do. You get players who are on the bench and sulk and then when they come on they are not likely to score a goal. Miki came on and was ready."