Those guns have three nearly identical screws at the bottom of the sideplate. One has a flat head to clear the stock, it goes to the rear. The other two look identical but one has to be a tad shorter and/or have a slight flattening at the tip to allow the crane to swing out. If both act the same in the front position, see if you can tell where the screw is rubbing and remove a SMALL amount of metal at that point. Like one file stroke. Then try it. You should not have to use more than two file strokes.
Note that usually, just working the crane in and out will do the job without any filing at all.