[Accelo]

Very difficult to tell the 4.8L from the 5.3's with out looking at the pistons.
The 8th digit on the vin will identify the motor if it's still in the vehicle.

Get the complete package, even a complete wrecked truck if you can.
That way everything fits. It will save you hours and $.

Many of the issues I had can be tracked directly to miss-matched parts.
Most the time they eventually fit.
My transmission as an example.
It was one year off and would bolt to the motor. However it required a different flex plate. So I purchased one and modified it and afterwards figured out it was the wrong flex plate offset. So back to the parts store for another. Easy to double your costs with mistakes like that.

Use a truck motor with the fan mounted on the water pump. Will save a lot of money and wiring hassles if you do.

Drive by wire can be easily converted to drive by cable. But there again you are changing stuff. Easy enough to just get the style you want and stay with it.
As a side note adding cruse is easy with drive by wire.

I also recommend purchasing the complete ECM and harness. One can modify the harness your self. Leave that for your second transplant. You will have enough issues.