On a scale of 1-10, 10 being the most diffiult. I'd honestly rate it about a 4.
I'm an office geek, who's somewhat mechanically inclined. The instructions are very well laid out, with a list of tools needed, and for the most part it's step by step follow the directions..
There are a couple of tips and tricks I would suggest.
1. I went to Staples and picked up the old fashion tags with the very small wire so I could tag everything I took off the vehicle and where it came from (cylinder 1 injector wire, coil wire and plug wire etc).. It would be tough to get those mixed up with the wire loom done very tightly, but just didn't want to worry about it.
2. Their are 3 factory cables that need new connectors to plug into extension harnesses, and pulling out the wires of the OEM connector to plug in to the new connector "DePinning" was something I'd never seen or done, so that took a few calls to Roush Tech, but once you see how, it's very easy.
3. The back bolt on the Supercharger was actually pretty easy, the trick for me was swapping out the sockets and extensions to get the correct height over the SC to appropriately torque it down. You don't have much room above the SC so the length from the torque wrench to the bolt was key.
4. The last item, and by far the most difficult was a single back bolt that is used to hang the 45 degree throttle spacer on the SC. That one was pretty much lay from the radiator all the way to the firewall with your left hand around the back of the SC to ensure you get the socket on the correct bolt while you're right hand steers the torque wrench and swivel to the bolt (a second person here would have been awesome).
5. The last little tip is around the brass vacuum fitting that installs into the InterCooler manifold for the Boost Gauge vacuum line. The instructions come as one set for every component. So, as you install the SC there isn't a instruction number that says "if you plan to run the boost gauge, installing the vacuum nipple with the InterCooler out of the car will make your life easier" than trying to do it with the InterCooler installed..
I was pretty proud that I could do this, and do it by myself. If you have a buddy and any mechanical skills I'm pretty confident anyone can do it.
---------- Post added at 08:11 AM ---------- Previous post was at 08:10 AM ----------
OH, PM if you want the SC instructions, I have those in PDF format so that you can review and get a feel for what it really takes.