My ademco 6139 has a 5 wire harness that plugs into the side. I purchased a 6160, but it only has 4 wires. The wires are NOT the same colors.

Hello all, I just recently bought a house and I'm new to the world of DIY. I have a decent bit of automotive knowledge so hopefully that translates. Anyways, I've had alot of break ins in my neighborhood and decided to invest in a wifi camera DVR system. I'm attempting to add 4 security cameras around the house. This is the first major project I've done to my house. The cameras are wireless (minus the power wire and ethernet if i opt to). The cameras are plugged into your typical electrical outlet. I'm trying to drill thru NO drywall. My plan of attack was to obviously cut off power in the area, remove the outlet from the wall, drill thru the brick, feed a wire thru to the outlet to get the power cord, then feed the power wire back up, attach the camera to wall, [u][b]and then splice the power plug into the outlet.[/b][/u] I was told by someone that i can splice that way into the outlet? I just want to confirm. I want to receive constant power. So I'm thinking if i take some wire nuts and wire into the hot, neutral, and ground wires, that it will work. If i can, do i run any risks such as fire hazard? The outlets i planned on doing this on wont be heavily used...maybe for a lamp or something. I'm used to wiring car stereos and it's almost anything goes so I just want to be sure or if i can't do it this way, what's a better alternative? Thanks in advance!