There is also the EFI to think about. The stock computer won't run the engine alone. There will be harness work and at least a little programming of the computer (remove security and a few other tied in things).
As much as getting the engine to fit under the hood looks to be the hard part, it's the 100 little things that will bite you in the end and any of those 100 little things is what makes the difference between a quality install and a hack install. Get 99 right and 1 wrong, and it's all wrong.