I'm more on the sloppy mechanics side of the spectrum, an ls engine will be the easiest engine to learn on. a few youtube videos and the resources here and you're good. the sloppy guys pull a 5.3 out of the scrap yard. they consider a 6.0 a oem race built engine lol. flip if over, check the main and rod bearing, grind some bigger gap in the rings if there's no bad scoring on the cyl, re-torque the mains and rods, new or some times even reuse head. gaskets. cam kit with new lifters. reuse every thing else, hang a turbo off it on e85 and make 800hp till it breaks a rod from getting greedy with to much boost at low rpm. I believe they have gone 8s in the 1/4 for $8k including the car.
if you're thinking of swapping the engine, I'll take it you have a garage to work in. some tools and don't mind buying anything else you might need.
with that, it depends on the motor. if you've heard it run and/or driven it. it's got good oil pressure and sounds good. I'd do a compresson check, look in at the cyl walls, as long as the look good and it's not a afm engine, which I believe the 6.0 isn't, which is the point of the swap. I'd do pan gasket, o ring. front balancer seal and balancer. the timing change will be your call based on results, ls2 one is the standard swap, but I don't know if that is correct for these trucks ecm. rear main/cover and send it. probably go another 150k or in a stock daily driver application without issues.
now if you buy one randomly already pulled. I'd go deeper. take a look at the rods and mains, do all the above plus a new high volume oil pump and probably have the heads checked at a machine shop. new lifters and guides, inspection the cam lobes really well. cam bearings, eh the high volume pump will cover it. or you can replace them. either at a shop or buy the tool and install them yourself. anything bad you find like worn mains, rods or cyl wall will add to your cost and be a decision made at the time. things can snow ball quickly if you get a blown up base to start with.
not sure there's a more enjoyable first engine to build thou,(besides maybe the Gen 1 sbc, did my first one of those at 16 years old from a book at the library) the amount of info and videos is endless and I don't think there's to many small gotches compared say something German. my buddy is a vw guy and watching him source parts and all the little special instructions that go along with those things would drive a 1st timer nuts.
as for what needs to be done wiring and tune side. Petethepug seems to be the go to for that. he's laid it all out for guys a few different times here.