onstar with system wire harness ?

ok, i have a customer (04 chevy truck) who went to someone else for a system and screwed him of his onstar. i've done the metra onstar harness before, but im confused because there are three different harnessess(vt gmos01,02,03). his truck came with the bose systembut all that it gone. he's running a panasonic in dash monitor with the separate brain going to a memphis belle amp. should i get the basic gmos01 harness?owner of

Motion Marine & Car Audio

the florida keys

hmm tricky, its hard to say since there have been some things changed....try each of them until one works..you can call onstar and have them run a test to make sure when you think you have it right....hmmm