Not to discourage editing.
BUT..Don't forget to check out the
"Swap Pages".
"Search", under "P-51", or "Mustang". There's Quiet a few! With retracts, and flaps.
Their editable also. Just make a copy, before editing,(for reference) and preserve the original. (Or just re-download to start over)
You may even find a closer match to your 42.8 inch, E-Flite P-51D "Dallas Doll"
Swap Page File Types: EA=Entire Aircraft, AV=Aircraft Variant, CS=Color Scheme,
AV and CS files, NEED the specified EA file, to be loaded, TO. On the download page, ALWAYS check the "Requires:", BEFORE, downloading. If you don't have the required EA for the AV, or, CS, get it. If the Required aircraft is in blue, and you don't have it, click it. That will take you to that download page.
Also check this edit.
https://forums.realflight.com/showpost.php?p=265116&postcount=9