I have found out that the stated cheat codes can be written in any way one likes. For instance in the streets mission I wrote xxxx-xxxx-xxx and I had the M16 rifle. Or it could be anything starting with XXXX and the M16 is unlocked.
The border crossing mission does not carry over M16 and the mission is too long - one mistake and you are back to wear you started, there are no saves and resume the game from the checkpoint.
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