General guidelines for tuning GM vehicles:

This template is for (5.3L)Z and (8.1L)G trucks only, the 5.3L T engine uses software B. Uses .CRG or .2CL file formats, 2CL to be used in Predator only. 2003 SOFTWARE A. Most common 2003 template, use 2003 C for recently flashed (mid 2004) Uses .CR3 or .3CL file formats, 3CL to be used in Predator only. 2003 SOFTWARE B ................
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