There's a couple of good ways to mask canopies. If you use tape - try using clear tape for the edges then masking tape for the center exposed portion. After the paint has dried, lighting score around the edges of the clear tape.
there is also liquid masking agent. Another way is to make your own liquid masking agent by using water , white glue and a drop or 2 of liquid soap.
To mask the texan canopy easily, try appling your mask in one direction first ie:
painting and sealing the vertical structure, then doing the same for the horizontal structure.
3d modelling is an option
a true mental excercise in frusrtation