Rear hub thread - damage

[Old Dave]

As part of my refurb of the RN Box I need to remove and refresh the hubs - the off-side one was straightforward, but the near-side has a damaged thread at the start which is preventing me screwing on the hub-puller.

I have heard of people using a triangular file or a junior hacksaw to clear the way but never had the confidence to attempt it.

See photo

Do clearing die exisit to save the day?

   

Any advice would be appreciated.