Too short clutch fork?

74 duster, 318 w/ 3-speed manual. Clutch fork seems to be a half inch too short. W/ trans installed to bell housing, releasing bearing won't stay seated on fork. One side of bearing will stay seated but other side comes off. Turn the bearing to seat the side that's off and then other side comes off. It's close, but trans shaft prevents full seating of both sides of bearing on fork at same time. Fork appears to be the right one. It measures 12 1/2" in length which I believed is the correct fork for this application and I don't know of a longer one for mopar. Fork appears NOT to be the original equipment because it has a sticker for another company on it, but as stated, seems to look the same as stock and correct length. Anybody else run into this? Something I'm missing? Solutions? Thanks