Hello from Louisiana

Hello, all I just recently joined and I am happy to be showing off my newest Mustang my 2004 40th Anniversary edition, pictured, while this is not the first I have ever owned it is the first I am wanting to do an engine swap with, so here is my question, it has the 3.8 I am sure you have already guessed, how difficult would it be to just swap an 04 GT engine into it, could I get away with just swapping the computers? or is it an entire wiring harness swap? I have a wrecked 04 GT however the trans and rear-end are already gone the harness has been scavenged from everywhere but the engine compartment so there is not much except engine, computer, and instrument cluster that I can use as far as mechanical goes, should I just keep the 3.8? I am retired Army and on a limited budget

Thank you for the video, this is exactly why I wanted to swap because one of the rockers broke almost in two, all of these bolt-ons are affordable for me and the exhaust signature sounds so much better, if the throttle response is what he says then I think I will stick with the 3.8 at least until I can afford to have a speed shop do the coyote swap for me