Ah bugger, mine are different to yours though, mine are a turnbuckle style arm. But would only fit in one way anyway, one end is slightly wider than the other.
Only thing I can think of is are the arms staggered the right way? As they look like ---> I they should be staggered so the upright is pulled foward as far as possible. The body end looks right, but cant really tell for the upright end. But seems a bit odd that the arms themselves would be around the wrong way...