Józef Dziobek

Hey guys, id better start from the beginning, I bought a 98/99 facelift wrx from a bloke who said nothing was wrong, later I found out the head gasket has a leak, so anyway I called my local subaru specialist and after having a chat to him he said with 245,000 on the clock im better off to buy a new short block, (unless I wanted to bore the cylinders,) and refurbishing the heads, for that work I got quoted 7k and immediately went in another direction. Ive found a 00" engine for 2.5k with 130 on the clock, still in the car running and I thoight that was a good option, I know the engine will bolt up, but can someone please explain the engine management path which I would need to take to get her in and running? much appreciated guys thankyou!