The long and short of LS swap

[Security guy]

I know there's a million threads on swapping an LS motor into a truck, but without reading a bunch of threads of how to do it, what is the short version? From what I know, you gotta have the motor mounts, oil pan, obviously the correct headers, transmission, etc.. The question I have is, do you need an oxygen sensor, the computer harness, the digital gauges, programming, fuel pump, etc to make it run? Would it not be more simple to put a carb on it and be done? The last time I messed with fuel injection, it was a major pain with all the electronic stuff involved just to get it to run. Have things become a little simplified from 10 years ago? And what's the over-all cost comparison? I know an LS motor could be gotten for just a little more than a traditional small block, but does all the other stuff add up to be way more than sticking in a 350? I had a 5.3 Silverado that ran awesome, but how many years of driving to get better mpg does it take to pay for the change to an ls motor? Just thinking out loud...