Rethreading the Door plates
 

I noticed at least two of the door bolts started spinning.

I plan on re-threading them to 7/16 x14.

do you guys have a better or different option?

Re: Rethreading the Door plates
 

I don't think you have another option except replacing the plate, and that requires some cutting and welding. I don't know if you will have to grind the heads down any or not.

LockDoc

Re: Rethreading the Door plates
 

Another option is to use a Heli-Coil or a solid body type threaded insert to repair the stripped out threads. This way you could keep the stock 3/8-NF threads and not have to worry about the fasteners not clearing the hinges.

The solid body type would be preferred as they are retained with tangs that are knocked in around the perimeter after you thread them in place. They are more money but would never come out with the bolt which is a possibility with a traditional style Heli-Coil insert.

I've installed literally thousands of these as an air frame fabricator and machinist for the Air Force. They are a great way to fix torn up threads in an old part.