The screamin eagle is the only bolt on programmable ignition that can take it to 8K. Most others you end up losing the auto enrichner which is imperative for me. I just won't cut corners that way.
However, it is obsolete now so its become very expensive, if you can even find it. So, many are forced to find alternatives like J-Lee.
Also, lets not forget that even if you changed your ignition you would have to have the necessary headwork that could take the upper rpms. So all in all it would be the ignition plus the headwork to take it that high.Cams would probably be a good idea as well.