How do I migrate to Bitcoin XT from Bitcoin Core?
The two clients are based off of the same code base. To use Bitcoin-XT, you only need to make sure your Bitcoin Core client is shut off when you start the Bitcoin-XT client. The two programs use the same data directory and wallets, so all your coins will still be there.

See "Should I be running Bitcoin Core or Bitcoin-XT?" for more info regarding the differences between the two software packages.

In the README.md of Bitcoin-XT, it even says:


  XT uses the same data directories as Core so you can easily switch back and forth.