Nissan 240SX Forum : “Rebuilding a Car/Motor”

Not really specific details but what goes into swapping anything to anything just comes down to: engine mounts, clearance issues, transmission and driveshaft. Test fitting is very essential for everything before you manufacture any parts, I've never seen a V6 in there besides a VQ/VG series but I wouldn't doubt that you can put one in there. The engine bay is big enough, the biggest problem probably would be clearance on the steering shaft, so use of custom ujoints may be required. A lot of planning and patience is another thing you're going to need. Good luck.