Brian,
Take a good look at the valve itself, under the dash for the lift. When I bought my twin stick 1450, the lever for the front ports would not move. The one for the lift worked fine, since it had been used regularly. I also discovered it needed ISO mounts, new pan to rail bolts and a pan. I took the tractor to Dad's and we pulled the engine. While the engine was out, it was easy to see the valve. If you moved the lever, you could see the shuttle in the valve would not budge. He soaked the shuttle for the next several days with Blaster and would tap on th shuttle lightly with a small brass hammer. It started to move, and once it moved, we were able to work the shuttle with the lever and it freed up. This was 10+ years ago and the valve still moves. During the summer, I make sure to move both levers once I in a while. In the winter it gets moved on a regular basis as I now have a hydro angle blade.