I just checked my D-2 and she has 5mm overlap on her spoiler plates, minimum is 3mm. With zero overlap, air loads could force one plate under the other and thereby lock both spoilers in the full open position.........don't you just hate it when that happens?

The G-103 had something similar where wear in the spoiler stops allowed the spoiler plate to extend above the wing skin. Air loads could then shove the plate aft, leaving it on top of the wing and..............the spoilers could not be retracted! This came to light when an American Airlines Captain who was moonlighting as a ride pilot at Truckee, found himself facing the cliff with both spoilers stuck wide open! Kool-Hand-Luke, kept his speed up and did a "bird-purch" onto the cliff! He and his passenger both walked away!
JJ