Bunk

Am I on the wrong website?

Subaru newb here making plans for a 97 (09/97) legacy. It has a couple blown headgaskets (still runs) so I was going to just swap in a jdm longblock and have a driver. Then the other day I had a genius thought so that brings me here. I can fab/machine parts etc but what im curious of is the relative ease of putting a sti engine/trans in. I know the gear ratios varied thru the years and that I may have a issue with the rear axle ratio, so buying a complete wrecked sti has run thru my mind(stronger axles etc)- that way I could swap struts etc over..but im thinking that a straight bolt up is a long shot...so im here to get educated. Is there a straightforward year sti to use to make the swap easier?(drivelines/front half shaft wise).. Thanks for any heads up, lots of searching to do