HSF3 installation difficulty

[stevh0]

I took a HSF3 out of my WRX STI before I sold it and I would like to install it on my Forester XT, before it goes for tuning.

Im very hands on and can install mostly everything (stereo's, turbo swaps etc)

On a scale of 0(easy)-10(oh balls) , how difficult would it be to install the HSF3 on my Forester (preferably want to do the ecu wiring too)