engine swap problem!!!!!!!

i currently have a 95 gs and i need to swap in a new engine. At first I was going for a 4g63t but i was told that they are very hard to install in a gs. So i x'ed that out and i was told that you can put a 94-95 evo engine in and it will fit right in the gs's engine bay with no problems except you have to "surface out" the wheel well and get a new ecu and harness. Is it true that you can put this engine in a gs with no prob? and what is "surfacing out" the wheel well? Any help would be great.

its not "No problem" You need a different transmission and custom mounts, its just as hard or harder than a GST swap because all the parts are harder to source