The way a friend and I did it or he did it was as you said, front fenders,but rt front on the left rear and vise versa,and add 2" in the middle.When you saw it all done it just looked right. I think the 2" was so the flare would center (start the same distance from were the front ended around the door). So 2 front fenders and 8" out of another one.
Hopefully yours is uncut, I'd be nice to start from scratch,and if not just a little more patching.
Looking back I opted for the bolt on flares because of intended off road use but it ended up being street use mostly.
Know matter how you do it, its tack em on see whats looks good to you.