The Lilywhites put themselves in the hat for the third round with a solid display that could have been a bigger margin.
North End opened the scoring 12 minutes in as Monakana converted, via a deflection from Gills skipper Adam Barrett, then Stuart Beavon converted after excellent pressure to close down the keeper by Lee Holmes just before the 40 minute mark.
Deon Burton missed a penalty in the opening minute of the second half for the visitors, but in reality this was a rare chance for the Medway side to get back into the game.
North End started the game with three changes to the side that started at Leyton Orient, with skipper John Mousinho returning to the side along with Thirsten Stuckmann and Monakana, back from the dead leg that kept him out of the trip to Brisbane Road.
The Lilywhites were on the front foot from the kick-off, as Monakana went on a mazy run from the centre circle, before being upended 40 yards out. From Nicky Wroe’s free kick Chris Robertson’s header back across goal could not be converted.
However, the home side had an early lead with 12 minutes on the clock. Another free kick from Wroe on right edge of box was delivered to the back post, after Lee Holmes had been hauled down by Adam Barrett.
The ball to back post for Paul Huntington, but his header came out; Chris Robertson missed with swing, but Jeffrey Monakana side-footed into top corner from 15 yards out.
The young winger was in dangerous form and four minutes later he crossed from left, which was flicked cleverly by Stuart Beavon just wide of the right hand posy from 15 yards out.
The visitors came into the game midway through the half and had their best chance of the game after 22 minutes, which required a good save from the returning Stuckmann to deny Romain Vincelot after a pull back from byline by full back Fish.
Just before the half hour mark the Gills keeper made a brilliant save. Tommy Forecast denied Beavon after great break by Monakana from his own penalty area to set up the frontman, whose shot was driven high and hard, but the stand-in keeper got strong hands to palm the ball away.
However, the No.29 wasn’t to be denied on 38 minutes. Brilliant hard work from Lee Holmes, closing down Callum Davies and then the keeper, he got a block on the custodian’s clearance and the ball came out to Stuart Beavon who calmly slotted the ball into the bottom right hand corner from the edge of the box.
Manager Graham Westley was forced into a change at the interval, Jack King on for Nicky Wroe, who had been injured in a tackle that led to a first half booking for Romain Vincelot.
The start of the second half was frenetic. Within a minute of the restart the visitors had a penalty. John Welsh was somehow adjudged to have blocked a shot with his arm as half-time sub Chris Whelpdale hit a shot from 25 yards. Deon Burton stepped up and hit the shot low to Stuckmann's right, but it struck the foot of the post and out.
North End cleared the ball for a corner, but from the corner Monakana broke with pace one-on-one with a defender down the middle. The No.17 raced away and was upended on the edge of the 'D''. It had to be a red card and a free kick to North End, but the referee, who was miles behind play, gave nothing!
Just two minutes later and North End struck the post themselves. Monakana again had burst down the left and shown real pace before feeding it into the feet on Beavon, who turned, spun and smashed a shot against the right hand post.
Thorsten Stuckmann then made two world class stops, one with an outstretched arm from a shot in the left hand channel and then with his legs from the resulting corner - as the opening ten minutes of the half were action-packed!
On 57 minutes King and Mousinho bust a gut to get on the end of another Monakana ball in from the left, but nother could get a good enough connection and directed the ball just wide of the right hand post from close range.
On 70 minutes North End had the ball in the net for the third time, however, this time the referee inexplicably ruled it out, saying Beavon's challenge on the keeper was a foul, when both slid in on a 50/50 ball!
The last 20 minutes was far more sedate that the opening 25 in the second half, the highlight being the 90th minute introduction of Lee Trundle for his North End debut.
PNE Line-Up: Stuckmann, Kane, Cansdell-Sherriff, Wroe (King, 46), Robertson, Huntington, Monakana (Trundle, 90), Welsh, Beavon, Mousinho (Procter, 74), Holmes. Subs not used: Simonsen, Sodje, Byrom, Procter, Hayhirst.
Gillingham Line-Up: Forecast, Fish, Martin (Lee, 46), Allen, Davies (Whelpdale, 46), Montrose, Birchall, Burton (Kedwell, 69), Weston, Barrett, Vincelot. Subs not used: Strevens, Jackman, Frampton, Flitney.
Attendance: 5,271 (444 away fans)
Referee: Mr T Kettle