It helps a bit, but I am talking pulling the LB7 out and putting the LBZ in.
If you're talking complete LBZ, ECM, TCM and such, stop there... Forget it. Will not happen unless you have EVERYTHING (and I DO mean EVERYTHING) from a doaner truck (
all harnesses, ECM, TCM, BCM, EBCM, Radio, Amp, Cluster, HVAC components, RSE if applicable, PDM, DDM, XM if applicable, Onstar if applicable, TCCM, probably a module or four that I'm forgetting), it
will not work. LB7 injectors won't work in the LBZ heads, you can't drive the LBZ injectors with the LB7 FICM. The ONLY thing you can use in your LB7 is the shortblock.
I'll be converting my 04 LLY to a LBZ ECM, TCM and motor, but an 03+ is WAAAAYYY different from the 01-02 trucks.