Nearly Finished my Kouki Rear end Swap

When I forgot that my Backing Plate and Dust Shield has this huge bump of rust popping out. I've asked a few friends what they think they say to cut out the rust and cut off the dust shield and she'll be sweet.

But I've read that you need a Dust shield to be road legal.

Just wondering what my options are.

Cheers

P.S Did a search didn't get far