Step 1. Install the Bitcoin Private Electrum Wallet
Install the wallet following these instructions, and create a new wallet.
Step 2. Go to Wallet - Private Keys - Sweep
Step 3. Enter your Private Keys
In this field, paste your private keys. Both Bitcoin Private Keys and Zclassic Private Keys work.
After entering all private keys you would like to import, press 'Sweep'.
The address mentioned there is the BTCP address they will be sent to. By default it is set to the address of your current wallet.
Please ensure you do not change this to another address in case you do not hold the private keys to that wallet.