[LS short box]

In regards to the arms I mocked the mounts for the spline bar and did some basic measuring for the arms. Bought the arms and had them bent cold at a local machine shop with a press. As I recall they have various arm lengths that be shorten as needed. Again it was a bit of trial and error but its not rocket science.
Keep in mind the spline bar from Speedway Engineering is hollow so shortening and res-splining might be a bit tricky.