How do I completely reset a GIT repo when I completely remake the entire project?
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I'm working on a project for a company, Well I was brought in to fix a project and ended up just remaking everything entirely. It was the only way, it's a game and most of the code was made with the first version of the engine and wouldn't fit with the newest version of the engine. So I've completely remade it, but it won't let me just push the changes when I delete everything and paste the new source in. 

I'm also not the main owner of the repository, it's the main guy at the company who has it in his bitbucket account. I do have read/write access though. I would of asked him to do some stuff for me but though he's the main guy he's only the main artist and not super technical. So I'd like to be able to do it all on my own without having to walk him through.

I just want to completely clear a project and paste in the new source and send it in and have that take the place of the old code on the main repository. Is there a way I can do this with git?