Are there any safe ways to claim BCC while keeping your current private keys usable safely? Most of my BTC was in my vanity address, which I would prefer to keep.

I'm thinking of getting Electron Cash, prevent it from connecting to the internet and maybe signing an offline transaction and than broadcasting it? Anyone know if that would work and the problems with it? Might also use BitcoinABC, sync it, block it's internet connection, import my keys and then signing an offline transaction.