Update - I went camping this past weekend and stumbled on the junction box. Of all places on the 351 it is located in the entertainment center! Yes you read it right - the bottom cabinet of the entertainment center. Puma did a good job of hiding the junction box. Now i am going to do some shopping around for an Onan Generator.
Quick recap for those looking to install a generator in a 351 - if you have fuel lines already run to the front in the battery compartment, a transfer switch located on the back of the circuit breaker, and a junction box in the bottom of your entertainment center then you are all set to install a generator like factory.
Thanks for the help everyone! Great forum