Hi Mark,
Just a suggestion, why bother with a rear fender. A stock seat (especially a flatter T-Bird one) looks quite cool without the fender. Aftermarket rear lights by motrax or oxford are quite easy to fit if you can make up a bracket. If positioned right, the number plate will catch a lot of road crud keeping your pillions back dry and clean.
This is what I've been aiming for with mine, I don't think I'm quite there yet as other things keep getting in the way.
And yes I know it's dirty, I'm going for the rat bike look
Wayne