Couple engine swap questions

[Grimmzda]

I found a smoking deal on a 2000 chevy 1500. I was told it has a 4.8 vortec engine. Unsure if its an ls or an lt1 though. Also no idea on the transmission. Any idea how to tell the engine or trans? Also if it is an lt1, will the trans and harness etc work for an ls engine if i find one down the road? Sorry for all the questions. You all have been a major help to me so far!

Just fyi, im doing my 72 c10 build by myself and im not super mechanically inclined. But i learn fast. So basically im doing what you guys suggest and using your knowledge to help further my own. So thank you all so very much!