Re: To "wing it" or Not...
Just a off center thought, I dont have any others; If you do attach the wing to your existing hatch, do a test fit and see if you like the color. It looks like the donor is black and you may find that appealing, if not you can pull it an paint it after you got the fit up to your level of quality.
If you swap the hatch you have a spare for swap or one for the other [weather] season.............Woody