Just curious if anyone has seen a LS conversion going this route???

 

On a converted FC/FD you are going to have a very tough time fitting that under the hood just like they did. Also, that much cast aluminium right at the top of the engine without a huge difference in throttle response and gains is going to be a tough sell. Most LS intakes clear the hood or require minimal modification, a MSD Airforce, FAST or LS3/7 intake are the popular ones folks switch to.