@gap, I hope you down load both mine and kapuhy's files to examine!
@kapuhy,
Using nothing but 010 editor to change your rudder,
I imported your rudder to the Avro GR2 file.
There is NO file size change to the GR2 file!
Look at the rudder size in your edited GR2 compared to mine!
I also opened my GR2 with Goblin.
Testing TDW's program I did remember a few things I forgot!
So this is going to be easier then I recalled!
I'll upload the test GR2 so you can see it for yourself.
https://www.mediafire.com/file/vypnt...test1.GR2/file