Sierra Steering Coupling Joint

[Wynand]

Im installing the steering column on my car now and have a Sierra unit. However, since it is to short I have to lenghten it so no sweat. The unit has a coupling joint I will use at the top of shaft at the steering wheel side and a funny coupling made with a rubber disc/link on the rack spline side that is flexible and acts sort of like a universal joint.

And this is my problem. From the engine bulkhead (bearing) to the steering rack spline is aboat 900mm odd and the mis-alignment longitudinal is about 135mm and gives an angle of about 8 degrees at the steering rack spline.
My question: can this rubber coupling joint be used as a universal joint at 8 degrees angle or do need to add another universal coupling before the rubber joint coupler?