Any tips for getting the plate off without damaging it even more?
I reckon you'll find that the fasteners for the plate are 'drive screws', like these:
![[Linked Image]](https://www.outdoorking-forum.com.au/forum/uploads/usergals/2016/02/full-5630-27165-drive_screws.jpg)
It's really hard to get them out without damaging what they hold - best bet, as seanw says, it to try centrepunching the head, and drilling it off.
If it's too hard to centrepunch, a very carefully used die grinder/Dremel type tool and a suitable stone would be the best bet, to remove the screw head.