Emma Follis got things started for the Royals before McGee and Lois Roche netted and Wildcats defender Jen Jennings scored an unfortunate own goal.
Follis bagged her second to round off the scoring and leave Reading with seven wins from their nine matches in the FA Women’s Super League with BT Sport.
The FA WSL 2 with BT Sport
Sunday 31 May, 2015
"It was really good, we’re progressing from each game and getting stronger and stronger. It’s great to be going into the break at the top of the league," said McGee.
"Keeping that clean sheet is very important and allied to scoring five goals, that win’s good for our goal difference.
"It leaves us in a really positive position going into the break for the World Cup."
While Reading will be in confident mood they won’t have it all their own way in the league with Doncaster Rovers Belles keeping pace after a 3-0 victory over Yeovil.
Leandra Little’s first-half effort gave Doncaster a slender lead at the break but they pulled further ahead through Courtney Sweetman-Kirk before Sue Smith sealed matters with a spot kick.
And Smith called on her team-mates to produce the same level of performance in every fixture to ensure they are top of the pile at the end of the season.
"We knew coming here that Yeovil are a fantastic team, who have done so well this year, and have got a lot of points off a lot of good teams," said Smith.
"Every game is huge, which is good for the league it makes it so competitive. So for every game, we just have to perform as well as we did today."
Elsewhere, Kayleigh Hines admitted the hard work paid off after she netted a late free-kick to save a point for Oxford United against Aston Villa.
Villa raced ahead thanks to an early effort from Katie Wilkinson before Amy West doubled the advantage after the break.
But Oxford kept fighting and Ella Franklin-Fraiture’s lob got them on the board before Hines’ free-kick stole a point.
"I practice set pieces because they are an important part of the game," she said.
"It's fair to say Villa were on top when they were 2-0 up just after half time but Ella then scored her first goal of the season to get us back into it."
And in the day’s other match Paige Williams set Everton on their way to a 3-0 win over Watford.
Williams netted after 33 minutes before Channy Boye-Hlorkah made it two and Michelle Hinnigan made sure the Toffees stay in touch with the leading pack.