Know how to add?
Toss in the cost of the mounts, K-member, headers, transmission crossmember, wiring, ecu, tuning and everything else just to make the 5.3 "fit" and "work" in a Ford car. Add that to the $2000 you had to pay for the truck with the engine. It's not as cheap as one would think, a well built 5.0 will go in a lot cheaper, and a 351+w with tuning will eat it's lunch for the same cost, almost always (almost)
A turbo 2.3 is usually about the same cost and honestly is more fun, though maybe not as "fast". You got any experience on ATV's? Remember the banshee? Thing was an absolute slug until it got up on the pipes, then it was like flipping the power switch on, tripled the power & torque instantly. Just like a 2.3 turbo at 20 psi....not necessarily fast but certainly puts a smile on your face.
Ain't seen a N/A LS (or 4.8/5.3/6.0) that is impressive, lot of guys pull them out of the junkyard throw a hair dryer on it and send it back to the junkyard all in one weekend, and still won't crack 10 second timeslips and yeah there are exceptions, just none around here
I have both a 2.3T swapped 93 coupe and a 92 GT with a 427" N/A SBF. I drive the coupe a LOT more, it's a lot more fun, though the GT is way faster. I can't use 1/2 of the power of the 427 on the streets, it's rough running (cammed obviously), noisy (though it does sound nice), uses a ton of fuel, but the 2.3 is slower, quieter, 30mpg, and honestly a sleeper....3" exhaust, you hear it but not loud by any means, people just laugh when the find out it's a 4 cylinder, then you annhiliate them to the next stoplight & make them feel bad. Don't get me wrong, I've had my butt handed to me many many times and don't care about it either, it's all good. But that little 4 cylinder puts a smile on my face every time I'm in it. I don't know how I ain't hurt it yet. Last week I busted the wastegate line and the first time I got into the throttle, it buried the 30 psi guage and I heard some pretty serious rattling before I could get my foot out of it, surprised it didn't bust the gasket or bend a rod or two. Reminds me I need to get the spare head into the shop for machining and crack test.