After rewriting the commit tree to rename the author and change the email, my local repo and remote origin are out of sync. I am the only developer and want to push my local rep
There's a setting on the remote repository that prevents (and it's a good thing) non-fast-forward pushes, that is the type of push you're doing.
As you point out you're safe to do non-ff push because you're the only one to work with it, so see this blog post to see how to change it:
ssh -t USER,PROJECT@shell.sourceforge.net create
/home/git/p/<project_name>/code.git
(filling in the correct project name)vi
and set denyNonFastforwards
to false