Well, since the S4 TII engines with the top mount intercooler fit under the hood of a REPU, I see no reason why the NA version wouldn't. You will need the front cover and oil pan off of the REPU to mount the engine.
maybe not oil pan, unless there is a different sump?
Front cover from any 12A (80's carb rx-7), or 13b gslse will work for front-mounts as well. Differences is the number of oil lines, 4 for the na 13b fi, 2 for the carbureted models.