Installing an alarm is no simple task. You want the alarm brain to be hidden well behind the dash as well as a backup battery and multiuple hidden sirens. Personally, I do my own custom fiberglass/wood fabrication, wiring, installation, etc. for the audio/video portion, but when it comes to the alarm I'd leave that to a real professional. Someone who has installed before and nows how to install it effectively.
As far as powering all of it, it really depends on your car. If you're running 1200 watts rms, you should be fine using a main line of 4 guage wire. Anything above that power, and I'd go for 2 guage, or even overkill it with 0 guage. Make sure you properly fuse the wiring as well.
If you experience problems with light dimming, I would upgrade the following connections under your hood with 4 guage wire: negative battery to chassis; engine to chassis; alternator to positive Battery. That usually fixes the problem and is cheaper than using an expensive power capacitor that store clerks will try to get you to buy.
If you're running a lot of power, and still having problems with too much strain on your electrical system upgrade your battery. Optima yellow tops are great deep cycle batteries. If you're
still having problems, go for a high output alternator. Seeing as this sounds like a daily driver, if you're having problems after adding a HO alternator, I'd be curious as to what exactly you're running
!
As far as bolting and stripping the bolts, it would be much simpler to take a hammer and flat head screw driver to the threads on the bolt. When you mess up the threads, it makes it pretty much impossoble to remove the bolt without taking a saw to it.
Also, when you bolt things down to the body of the car, make sure to seal around them with silicone to prevent water from entering the car.
Have fun
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