I discovered two errors (or anomalies :) ) in the USA strategy guide. There seems to miss some infantry in order to exactly do what’s stated.
In Early 1940, the strategy guide states that the US transport in sz 101 should pick up two infantry, but there are only two infantry bordering sz 101, the one in CUS, and the one in EUS. And the one in CUS is ordered to move to WUS in that same turn. So that means only one infantry can be transported.
In Early 1941, the strategy guide says that the US player should upgrade three of its infantry in WUS to US Marines, but there are only two infantry in WUS at that point. There start two infantry in WUS, one of them moves to Hawaii with an AA, but the CUS infantry moves to WUS, so that makes it two. Next turn, a transport picks up the two infantry and moves to Aleutian islands with it, but the infantry in Mexico move to WUS, so that makes it again two. But the turn after that you cannot upgrade three infantry, since there are only two.