hemi wireharness cut/splice ?

I have done exactly what you are considering using a 5.7 engine and 545RFE transmission from a 2005 Dodge Ram 2500. I got all the wiring with the engine and trans so I decided to give it a try.

If you have the skill and time I personally think it is definitely worth the cost savings. For some they can spend more time at work make more money and spend it on their project. For me I can spend more time doing the work myself to allow me to spend money on other parts of the project and get the car on the road sooner.

I had to read the factory service manual wiring diagrams to determine where each extra wire comes from and goes to then add the appropriate fuse, relay, power source, ground, etc. connection. I basically laid all the wiring out in a spare bedroom and worked on it off and on for a couple hours at a time in the evening during the course of one winter. Would I do it again? YES! Would I recommend it to others? For most people that would answer would be no. I have a good friend that is a mechanical engineer that would never have the patience for it, but for me it was a relaxing escape from work. It ultimately depends on your skill level and what you like to do. Do you like challenges and want to spend time learning how to read and decode the wiring diagrams? If so then go for it. If not, just buy one.

To get your car running you need all the wiring harness that connects to the engine and computer. There are four plugs that connect to the computer for the engine and transmission. For me alot of the cutting and splicing centered around wires that went through the stock truck's fuse and relay block. Lots of wires were removed in the process.

Not all computers have the security. Luckly mine did not so I have not had it programmed yet and currently the only trouble codes that come up are for no gauge cluster, no ABS speed signal, and no rear O2 sensors. I added resistors to a few circuits to trick the computer into thinking things like the fan relay, cruise control are still present.

Here's an older post with a summary of the circuits that I needed a fuse or relay for.
http://www.forabodiesonly.com/mopar/showpost.php?p=1105896&postcount=47