[Roundsworth]

Hi, Don! Welcome aboard. Is 'Mark 23 ' stamped on the gun somewhere? As for removing the forend wedge, the right end of it should have a single groove to facilitate starting it with your thumbnail. The wedge is a friction fit, although decades of non-removal might make it a bit more difficult to slide from right to left. A small screw retains the wedge from coming completely out of the forend. Push the wedge out so you can grab a hold of it and pull it out the rest of the way until it stops. The forend should have a tab, or projection, on the tip to facilitate pulling it off. Cheers!