If you want to be safe, run it on another PC. If you don't have a spare PC and your current computer's specs are not bad, you can try installing virtual machine on it, install OS in the virtual machine and install the Electron Cash wallet there. This way you would effectively separate two wallets while technically still running them on the same PC.
Can you explain how this would work? Has anyone here done this and is it easy or not?
easy is a matter of perception!
let me try to put it into steps for you, using a virtual machine OR a live linux:
1.a. download a Linux distro that you like. it can be the popular Ubuntu.
2.a. burn the distro on a DVD or if you can just put it on a USB and boot from that.
1.b. download a virtual machine program such as VirtualBox (it works for all OS, Windows, linux, mac,..)
2.b. install it on your computer and then build a virtual machine on it (it will be a window which you open but it runs a complete OS)
3. download Electron cash and install it.
optional but preferable: move all your bitcoins to a new wallet (not just a new address since Electrum is HD and your seed is all your addresses/keys)
4. import your private keys or just use your Seed to recover your BCH in Electron Cash.
5. Spend?