BU implementation for Bitcoin Cash:
https://www.bitcoinunlimited.info/download
Under "Bitcoin Cash Release".
AFAIK that should work seamlessly with your current wallet. (btw, I guess classic and BitcoinABC might be able to work with the wallet file as well, but I'm not sure.)
Can't speak from first hand experience though, I never used any of the full node software as a wallet.
Be careful and know what you do at every step (I'd use two different users for the two currencies as a start and just copy the wallet file.)