luke strawwalker's latest NASA report summary is of the "Modified Launch Vehicle (MLV) Saturn V Improvement Study Composite Summary Report" from July 1965. Here are figures showing configurations with 1) a NERVA nuclear upper stage, and 2) four strap-on 120 inch SRBs. Muahahaha!
Since my original post, luke added a lot more material, including the following digram, which is an 'orphan' from an unknown source. Not the option for strap ons AND a NERVA upper stage.