Wow, I have never seen a subject that has so many differing opinions! And now I will add mine....
Seems I have read that the nikasil plating is pretty thin and that neither bar-type hones or ball type are recommended because of the chance of wearing through. Scotchbrite is what was recommended and like Brian VT said muriatic acid to remove any aluminum that may be present (use appropriate safety precautions). That being said I tried scotch brite and didn't have any luck whatsoever trying to make things look the way "I thought" it should and I didn't have any aluminum to try to clean off.
If there is any cylinder taper top to bottom a bar-type hone will not clean it up until you come close to (or do) wear through the plating. That leaves the ball hone which does a good job as long as all you do is de-glaze just as gasgasman said. It will also clean uneven surfaces (cylinder taper). I have also used bar hones with a scotchbrite pad between the hone and the cylinder and that works good too. You just have to remember you are just trying to deglaze, not bore to the next size! And use plenty of clean lube.