even if it wasnt the intake is exactly the same just change it over to the 6.0 easy swap if u have any mechanical know how i did it from start to finish in 8-9 hrs.

 

I did mine last year,04 Avalanche 5.3L to a 04 6.0L LQ9.The only thing I changed was the oil pressure switch,for sme reason the one from the LQ9 was reading wrong.I also reflashed the PCM to a 6.0L.I also change the cam and spring while the 6.0L was on the engine stand.Works way better,fuel mileage is the same if not better than the 5.3L.