I hope you got the CJM billet top hat and not another plastic OEM one
I haven't torn into my fuel system yet even though I know my top hat is broken, so I'm no expert. But I'm pretty sure I drove around (still fairly aggressively) with a busted top hat for nearly 10K before parking the car last year. All of the elements there are intended to be exposed to gas, so I think you're probably ok. Someone like Charles at CJM would have more knowledgeable insight.
As for the half tank, you'll just need to siphon it. I've heard people say it can be a pain to siphon through the gas fill neck but it's certainly easy from inside the vehicle once you get to it. Just have a fan handy to help clear out the fumes.