I only used two layers. It was thick enough, didn't want them too bulky. What I did is I used the actual housing as the mold. I took off the headlight housing and covered it with Duct tape, yes Duct Tape. Take in mind that the fiberglass resin will want to eat through the tape. I put two to three layers of Duct tape on though. I tested it on a piece of board and the tape was fine at the bottom when the resin hardened with two layers but I used three to be safe. Tape what you don't want to get dirty cuz this stuff will run everywhere.
After you tape just lay the fiber glass and add the resin mixed with the hardener. Take in mind depending on how much catalyst you add will harden quicker if you add more but will get really hot and may burn you. Could even catch fire. Let it sit til it starts to get hard and then when you notice its hardening lay the second layer on so it sticks better to the first layer.
After it starts to get hard to the point where it is feeling like one piece, start to pry it slowly little by little til it starts unsticking off the housing. One thing I was glad I did was place those two extra layers of tape. Those two extra layers helped in taking off the hardened resin cuz it started to unstick from the actual tape from the first layer to the second layer. Also start prying when it is still a bit soft so you have some give on the fiberglass. Just be careful not to used something sharp when prying near the lens. Try starting from the outside first.
After you take it off it will be very easy to pull the inside tape off the finished product.
After that, make a template on how you want it to look but don't forget to lay the fiberglass bigger than the actual size you want so you can fine adjust it when you start to cut, sand, and grind. I used a Dremel with a sanding bit to smoth the edges out.
What I also used to make the sanding a lot easier was a medium size belt sander. That really helped in smoothing out the actual surface. Just rock it back and forth on the belt sander. You will be able to see through the fiberglass when you are sanding the bottom from the top. It is see through to a point. You can see the low spots on the surface where it is sanding so you know where to concentrate more on to make it smoth. You can also sand it by hand but it will take longer.
Depending how you lay the fiberglass is how much sanding you have to do to get it to look smooth. Remember not to go to far down since it is only two layers. It still looks to thick for me with just two layers but you can't even tell when it is installed on the car.
Oh yea, if anyone wants to try this for themselves I am not responsible if you damage your housing or if you hurt yourself with the resin or fiberglass because of my instruction. It will not at all hurt the housing if taped right. It didn't damage mine but be careful.
Hope this helps you out. I would have taken pictures but never thought about it til now. Lets see what I can do. My brother has a P5, maybe I can use his as an example. (2thumbs)
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