I can put any model software and any VIN on to the PCM. For Ben I'll load a VYII (04 model) operating system, but change the last 6 digits of the VIN to match his CR chassis number. That way if they do check it, they will find that it's definitely a 04 model PCM. Of course while I'm in there I may make some other "enhancements" as well...
On the subject of LS1 engines, 99 - 04 have three different variants.
This is for Australian delivered engines.
99 and 00 are LS1's.
01 - 03 are LS6's
04 is an LS6 with a slightly different cam profile.
99 and 00 use a 256k program (no lean cruise function, only one VE table etc.).
01 - 04 use a 512k program.
05 uses a 1024k program (for electronic throttle and other things).
Cheers,
Plums.