Rear Spoiler Install BY Austn Vert

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Hi to all,

To put or not to put a rear spoiler on the trunk of a '71-'73 Mustang Convertible. That is the question. Some guys like the look, others don't. I chose to go ahead with the project.

I bought a fibreglass one because of less tendancy to bend, distort etc.

They are heavy though. I heard plastic can play up in that regard. On the install, your two placement measurements are front/back and side/side.After much research, the proper favoured posi is having the back edge of the spoiler line up with the back edge of the trunk vertical edge. I have seen many variations with the front/back placement though. Remember, the fat, thick edge of the spoiler, faces towards the front of the car, while the thinner back edge faces towards back.Instructions come with spoiler and explain it all well. The spoiler should be set on a level angle, maybe slightly angled down towards the front. (check with level)

There are two spacer rubber feet that the pedastals sit on the trunk.I chose 14 1/4 inches from front edge of lid to front face of rubber feet, and 3 1/8 inches from back of rubber foot to back edge of lid.This will give you an accurate front/back placement of the spoiler with the back edge of spoiler lining up with back edge of trunk.Side aside will of coarse be equidistant and should come in at 8 3/8 inches from side of foot rubber to side edge of trunk lid.

The pedastals get installed to the spoiler before you mount the whole thing to the trunk lid. You will need shaped bolt spacers behind the trunk lid, as where the bolts come through the underside of the lid, the steel has uneven profiles. I bought pine dowel from my hardware store about an inch thick, cut it into small sections, drilled out the centers, and sanded each section down to match the angled profile of each of the four bolts.I sprayed them matt black.(See my photos) That worked well. Don't overtighten bolts when fixing spoiler to lid as you will easily distort the trunk suface.

Refinishing is a must for good looks and is a real bugger to do. Painting fibreglass was never easy to start with. My spoiler had a real uneven wobbly finish to it. I fixed that by using a long sanding block with 80 grit paper, and broard sanded it down first to help level it out. Several coats of 2k putty followed. That was long blocked as well. A couple more coats of putty and a block sand down with 240 grade paper followed. A guide coat and sand down with 800wet/dry to finish. I choose quality black satin acrylic lacquer to finish with over a more durable 2 pak black because if i got junk in the paint while i was spraying, i could easily sand it out as i was going. You can't do that with 2 pak matt and satin black.The finished result looks pretty decent i think. See photos on photobucket.and press any image to enlarge.

That's about it. I like the whole thing.

Thanks to all.


FOOTNOTE- By the way folks, you are looking at the original factory paint finish inside and out (Gold Glow Metallic) in these photos. The paint is still in fantastic condition given the car's age.The car originally comes from Ohio, where the first owner who owned it from '73 to 2009, hardly drove the car and kept it garaged all the time. Also, forget color matching from photos as if you look at mine, the color of the car changes dramatically between the shots. Never trust photos for accuracy.;)

Your reference for the pictures ..................................

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