I don't recommend bothering with harvesting the coins because only the main chain will survive but if you want to you sure can.

All you have to do is keep a copy of your wallet.dat pre-fork and keep a node running on the pre-fork chain. This will preserve your pre-fork coins on the pre-fork chain.

You will also need a wallet.dat on the post fork node and it must stay on the post fork chain. This will maintain your post fork coins on the new chain if that makes sense.

Keep in mind we are not Bitcoin and the old chain will die a miserable and wretched grizzly horrific catastrophic morbid toxic eternal extinction-level-event death with no supporting seed nodes, community, development, website, tender loving care, etc., etc.