Railroad Model Craftsman magazine recently published my Test Track review of Rapido Trains’ Toronto Transit Commission “Gloucester” subway cars, I mentioned that separating the permanently-coupled pairs is easier if one uses tweezers to squeeze the shank at one end of the drawbar. (I call it a drawbar because that’s how it functions, even though it looks like a pair of couplers.) This is also useful if one wants to remove a coupler from either end of a two-car set.
I realized a photo might help, so here it is:
As the image shows, the couplers have a split shank with prongs. These slide through the draft gear box then snap open at the back of the box, locking the coupler in place. There’s just enough room to slide fine tweezers between the truck and the draft gear, to squeeze the pronged ends while pulling the coupler (or drawbar) out from the front.
The Model Railway Show 