I use 3M 8115 panel adhesive. It takes an hour or so to set up, so there is some working time. I wouldn't do this on a hot day, because the glue will set up faster. Wear latex gloves because the glue will be messy. Here are some basic steps to glue door skins on:
Remove the trim panel, moldings, mirror, trim, glass, handle, etc.
Remove the door and place on a stand door skin side up.
Grind the front,lower and rear edge just enough to remove the portion of the skin that is crimped over.
Drill out any spot welds with an 8mm spot weld drill bit.
By now, the outer skin should start to loosen up. A wide,flat chisel and hammer may be needed to loosen it from the door frame.
After skin is removed, grind the surface where the panel will be touching the door frame, especially on the back side where the crimped edge will be. Hammer and dolly any wavy or bent areas on the door frame.
Dry fit the new skin and vise grip in place. Now is a good time to fit the door to the car. Some Novas have welded hinges, so it is critical that the skin is positioned correctly. Sometimes, I drill 1/8" holes for screws through the skin and door frame so positioning after gluing will be easier.
Remove the door, place on stand, remove the skin, use an acid brush to apply a thin coat of adhesive to all bare metal on the door frame. Apply a 3/16" bead of adhesive on the underside outer edge of the door skin. It is not necessary to grind the black coating off of the skin.
Place the skin back on the frame and secure with vise grips and screws. Use a body hammer and flat dolly to crimp the edge over. It is important to always hit the hammer where the dolly is so the skin is not damaged. If possible, place door back on car after crimping to make sure the skin is positioned correctly. If the door has twisted slightly, now is the time to remove the twist by placing a rubber hammer between the door and jamb. The rubber hammer will go where the door is in too far, and you will push where the door is out too far. After the door fits, leave it until the next day. This will give the adhesive plenty of time to dry.
Good luck!