if you are unfimiliar with wiring this site has all the info tips and tricks that you could think of.
Also if you have the factory alarm you can take the wire from the hood pin, extend it and tap it into the purple wire right inside the driver side dash end piece that pops off so if the hood is opened the alarm will go off as it should have been done from the factory.
You can also run a pair of 55watt back up lights off the factory reverse light wire with no I'll effects. Been running mine for over a year and no issue and tested the draw with a volt meter and it didn't cause a drain surge.
As for wire connections, solder, electric grease, heat shrink tubing or the paint on tape stuff and I always go back and wrap with electrical tape for added protection. I installed custom and show stereo and alarm through my 20's and am very OCD so use your imagination.
When soldering it is just like brazing copper so you don't get a cold joint that corrodes:
strip the wire and then hold a wire in each hand and then twist them together where it look like the wire just had the insulation cut off and there is no need to wrap the wire over the insulation but no biggie if you do, don't forget to put heatshrink on before you twist them.
Let the solder iron get hot, place the tip against ( I like under) the twisted wire and occasionally touch the solder to the WIRE not the tip, when the wire is hot enough it will literally suck the solder into the wire and it will not take much, after it is all silver I will then slide the tip back and fourth to make sure it is good to go.
Wait for it to cool then apply grease if you want, just a little bit, then slide the heatshrink over and heat it. If it's not cool the end of the hs will srink and you can't get it over the wire.
Scotch locks and t-taps suck as they end up breaking the wire and the wiring in the jk is too thin as it is, butt or crimp connectors are great for quick fix but never make the long haul in moist or humid conditions unless you crimp then solder. I know many will argue this and give testimonials but at well over 2000 alarm installs and warranty work I can tell you what will last and what will not and I am the type when I install something I never want to have to go back and f... Tinker with it.
If I can ever help please let me know.