Note that the twin cam hub knuckles use a different size bolt (larger) to attach to the struts. Also, the width of the part that bolts to the strut is different, ie wider then the sohc units.
Apart from that, i noticed no difference to the track of the front wheels after putting twin cam suspension in the front of my sohc AE82. (struts and hub knuckles. the lower control arms are identical between models)