The Clear & Delete should not have been required, but it you did need to redo guided setup.
Remember that InstantCake installs a complete new image to your hard drive. I believe the notes mentioning that you would not have to redo guided setup with PTVNet are for the person who is just adding it to a current drive, not when it is being used in combination with InstantCake.
As far as your phone line question, as long as you answered no to the phone line question during installation, you should be able to leave it connected.
Check the articles on this forum for the one about upgrading using the slicer to find out how to force a call. Notice that the method is different between 3.1.5f and some of the newer 6.3 versions.


RSS
Also, when I do the guided setup after the Clear and Delete Everything, can I connect the phone line? I chose NO phone line during the installation process. Can I still force a call? Thanks a lot.
R