somewhatfoolish

Hello from a noob; apologies for the fairly outrageous first post asking for hard-won knowledge.

My brother gave me his 2002 (SF) Turbo Forester a couple of months ago as he fancied a change and had bought himself a shiny STi; it's fairly sheddy and inspection on a hoist reveals the need for a lot of welding underneath and numerous things needing replaced to get through an MoT, so scrapping or breaking for spares is going to happen. There's a 2003 (SG) Forester 2litre XT not far from me with no engine but is described as sound otherwise; is my engine(EJ205NWVBB) going to fit in and play nicely with SG electrics? I've done engine swaps on 2CVs, minis and landrovers before now so the nuts and bolts hold no fears but the electric string is an unknown and intimidating quantity.