You will need to adjust the shape of the shield to match the polygons, or else it will just look odd, also you need to remember the icon for the shield, needs to match the in-game one, and also the one in the shop to buy!
I have been playing Zelda practically non-stop for the past 4 days, so I havnt done any more work yet, but after playing it, i will have a better feel for it, but i wont do a direct copy, as it needs to stay true to Ocarina of Time, as well as have the influence of Twilight Princess.