It's easy if you use smooth molding front and rear fascias. You'll just have to do something with the GT emblem that is integrated into the molding on the rear.
I took a slightly different route and used ribbed aero nose and GT fastback rear fascia. I had to trim the ribbed molding off of the fascia (the smooth marker light has the molding made onto it, the ribbed trim aero nose has it molded onto the fascia) and replace the arrowheads with the smooth type. On the rear, I used the notchie aero fascia support bracket, but trimmed the ends so the smooth trim (fastback) fascia would fit properly and had to notch out an area for the GT emblem recess to fit. I also had to use some washers to space the bracket out slightly on the ends to match the shape of the notchie taillights. I then had Paul McKibben (fierosails) make an SE decal to match the sail panels, but fit on the GT emblem integrated into the molding. I painted it black, put the decal on and clearcoated it.
Sound simple? I don'y have any pics and the car is in a million pieces at the moment.
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1986 SE Aero coupe.
3.4 DOHC swap is complete and running, now just have to finish the rest of the car...