The Yorkshire side will face treble-chasing MJSL champions Haroldeans, who edged past Maccabi Manchester Blue in their semi-final to progress. The final will take place at Salford FC on May 21.
A fortnight earlier the rivals will stage a dress rehearsal when they contest for the Harold Feldman Trophy.
But Leeds needed penalties to ensure their passage in the Shonn, seeing off Maccabi Manchester Yellow after a tense last-four clash which ended 1-1.
Moishe Hasid's controversial header cancelled out Dean Shaw's opener and nothing could separate the two teams. It went down to spot-kicks with Leeds holding their nerve to win 7-6.
But Leeds boss Kristall pointed the Yellows equaliser that never was for ensuring a dramatic conclusion was needed.
He said: "A lot went against us. We missed a penalty at 0-0 and then they scored - even though the ball did not cross the line.
"That was clear to see. We might have feared the worst but nobody felt sorry for themselves and we deservedly went on to draw level in stoppage time before winning it."
Haroldeans required less drama to win 4-2 against Maccabi Manchester Blue at Brooklands. Paul Harris, Bobby Fishel, Max Barnett and Adam Shiffman were on target for the Merseysiders. Roy Fux and Charlie Simpson netted consolations for the Blues.
Haroldeans boss Mike Bloomberg said: "We will keep our focus. Although it's one down in the league, there's still two big cup competitions to go. And we feel confident we can finish the job off."
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