Town head into the game full of confidence after winning five and drawing one of their past six league games, to pick up 16 points out of a possible 18 in the Combined Counties Premier Division South.
The impressive form started when Farnham won the reverse fixture 2-1 at home to Badshot Lea last month, and Johnson is hoping his side can complete the double to claim the local bragging rights again.
“Badshot Lea is a big one – there should be a big crowd, they’re going for the league title and we want to put a dent in it, so it will be good,” said Johnson.
“We’ve got nothing to lose – we’ll go out and we’ll go at them for 90 minutes.
“We did Badshot Lea the first time. Fordy said congratulations for winning our cup final – so he’s got a chance to get revenge for that.”
Farnham head into the game in confident mood after comfortably beating Redhill 4-1 on Tuesday night.
That result followed an impressive comeback from 2-0 down at Knaphill on Saturday afternoon to draw 2-2 and rescue a point. Farnham scored a stoppage-time equaliser to earn a point in the Combined Counties Premier Division South encounter.
Town found themselves 2-0 down against the run of play, but Lewis Flatman pulled a goal back in the 82nd minute when he swivelled and finished in the box.
Owen Dean equalised on 93 minutes with a superb header from Shamal Edwards’ inviting cross to the back post.
Town had scored stoppage-time winners against Balham and Jersey Bulls in their previous two league games.
“We scored with the last kick of the game and showed great character,” said Johnson.
“It was a good header from Owen – we love Fergie time.
“He did well to last the game as he was taken out in the first minute – it should have been a red card. A red card is a red card – it doesn’t matter if it’s the first minute. He managed to get through the game.
“Bar that decision, the referee was one of the best we’ve had, to be fair.
“We were the better team and should have won.
“Knaphill scored their first goal from a second phase. In the second half they scored from their only chance.
“We were wondering how we were 2-0 down.”
Despite rescuing a point late on, Johnson was pleased to see his side acknowledge they had missed out on a potential victory at Knaphill.
“When the lads first came in the dressing room they were delighted, but when reality set in it was two points dropped and they were disappointed,” said Johnson.
“That’s a good reaction to see as it is easy to think you can carry on after a late goal.”
Next up for Farnham is a home game against Camberley Town in the Combined Counties Premier Division South on Saturday afternoon (3pm), before they travel to Badshot Lea.
Town drew 2-2 at Camberley in the reverse league fixture in February, a game in which they led twice, and Johnson is targeting three points to keep his team’s momentum going.
“With Camberley and Badshot Lea we’ve got a big weekend,” said Johnson.
“It’s two derbies and we’ll ask the same of the boys again – to go full throttle. We should have won at Camberley – they scored late that night but it was a game we should have wrapped up. We’ll look to get three points in that one.
“We just want the games coming thick and fast like they are, and to pick up as many points as we can.”
Badshot Lea co-manager Gavin Smith is expecting a tough game against Farnham, but is concentrating on Saturday’s Combined Counties Premier Division South trip to AFC Croydon Athletic.
“We need to concentrate on Croydon first,” he said.
“Hopefully we can get three points and come through it with no injuries, and then we’ll look at the Farnham game.”