What isn't clear?
Step 1. Create a new Electrum wallet.
Step 2. Send BTC coins from old wallet #1 to new wallet.
Step 3. Send BTC coins from old wallet #2 to new wallet.
Step 4. Create a new ElectronCash wallet #1 using seed from old Electrum wallet #1.
Step 5. Create a new ElectronCash wallet #2 using seed from old Electrum wallet #2.
Step 6. Create a new ElectronCash wallet #3.
Step 7. Send BCH coins from ElectronCash wallet #1 to ElectronCash #3.
Step 8. Send BCH coins from ElectronCash wallet #2 to ElectronCash #3.
You now have new Electrum wallet with all your BTC and ElectronCash wallet #3 that has all your BCH.