Hint: That's a pretty interesting grid design, no?
Hint: Looks like 3 large plus signs there in the center.
Hint: Wait a minute! Maybe those plus signs are related to the mechanism somehow?!
Hint: Sure, those pluses represent the conjunction "AND", so I'm probably supposed to join things (maybe in two different directions).
Hint:
How about that! Those 6 pairs of linked grid entries actually fit 6 other clues. (Be careful with one of them, though. )