Leer Truck Anyone Know How To Replace A Leer Cap Rotary Latch?

Anyone know how to replace a Leer Cap Rotary Latch? - leer truck

Try to replace the latch on the left side of my truck cap reading. Theres a bar that appears a screw that has a slit at the beginning. When you activate the lock, the mother back to her .. the slot of the mother seems as if he could insert a screwdriver, but I turn the lock. WD40 and tried to use other products, the release of the locking nut with the slots. Is there a special tool?