As per the official release notes on Electrum:
https://electrum.org/bcc.txtI'm glad i found this, as it mentions that this should be done "after" the fork.
How to redeem my BCC?
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BCC wallets will require you to import your seed or your private keys,
which can be exported from Electrum. Doing so will expose all your
Bitcoin funds associated with that seed to the BCC wallet you decide
to use.
Therefore, *after* the BCC fork, but *before* you enter a seed or
private key in a BCC wallet, you should move all your funds to a new
Electrum wallet, with a new seed. You will still be able to use the
old seed or private key with BCC, because BCC has replay
protection. Wait until your funds are confirmed in your new Bitcoin
wallet, before you enter the old private key in a BCC wallet. This
will protect your BTC funds from rogue/untrusted software.
This link also explains the procedure in more detail:
https://www.reddit.com/r/Electrum/comments/6pu0lo/claiming_bcc_from_existing_electrum_wallet/