aautomaan,

Not sure I understand the question but let me try to explain...

For the most part, the difference in hookup logistics will be simply stacking all channels together and clip them to battery negative as opposed to only needing to ground one channel.  Hooked up this way, the 4425 can be used just as you would a 4423.

However, it does open up some options we didn't have before.  You can have your channel grounds at different locations without crossing things up.  The limitation here is that you would not want more than a 30v difference between these channel grounds.  So, for example, it would not be advisable to place a channel across an ignition coil with the channel ground on the negative side as that is going to kick 400v.  We have done this though and the scope survived but we were trying to find out if we could destroy it by doing that.

I would reserve placing a channel ground on anything but bat neg unless you understand the circuit and what you are trying to accomplish.  The example of a throttle body motor above is a good use for this technique as the channel ground voltage differential does not exceed 30v and it allows us to see the throttle body motor switching polarity in a way we have not been able to with previous models.

Hope that answers your question.

You could try to sell what you have on ebay or iatn, unfortunately if you want to move it you will probably have to take a little bit of a loss.