Can I softmod a 1.6b and use a HD that I have already duped?

I have a friend that is headed out of state and does not have time to order a modchip. I have installed plenty of chips, but I have never softmodded, so hang with me a sec.

First, are there problems with softmodding a 1.6b?

Secondly, I duped a 250GB drive, using my Xenium ICE. After I perform a softmod on his new 1.6b, could I use the duped HD with it? It is probably a stupid question, I know. I was thinking I could just softmod the factory drive and then use my modded box to transfer/replace the folders on the aftermarket drive and save its F and G partitions. Would this work?

Is there a better solution? I just didn't want to start over transferring all of the apps and stuff.