After beating Farsley Celtic 3-0 and Chester 4-0, Cox has enjoyed a thrilling honeymoon period in the Pilgrims dug-out.
But Saturday's trip to Edgar Street (KO 3pm) will be the new manager's toughest test yet as Josh Gowling's side sit just four points behind Boston, and will be keen to close the gap on the team occupying the final play-off spot.
"They're a good side. There's no easy games here," Cox said.
"The league from top to bottom is tough. We want an, understanding home or away, we've got to earn the right to win and I know we've got good players who can do that."
Cox praised his side for doing the 'horrible' stuff against Chester as they secured their second clean sheet of the week.
Now he wants more of the same.
He added: "Sometimes you need to win ugly, 1-0s away from home, to win championships and that's what I want to get over to this group.
"We can't go out there and play beautiful football and open people up, there's too many good teams at this level who don't allow you to.
"When we can play we can play and when we need to battle we can battle."
The Bulls have enjoyed a renaissance since their 2-0 defeat at Boston in October.
After leaving Pilgrim Way looking like relegation battlers they won their next five league matches and have secured eight victories and a draw from the past 13 games to climb the National League North table to 10th.
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