I just did the two two front doors so far as they are the ones I use most of the time, and I am getting enough heat for working on the car every weekend. I used the universal actuators and just secured them to the door in the lower right hand corner. I didn't have to use the strap. I just wired it up to the relay that came with the kit and now it works with the remote and when the car reaches 2.5 x idle in RPM it locks, and when the key is turned off it unlocks. I wnat to do the hatch next, but it isn't that important.