If you bought him from the scout list, it is unlikely that he will be able to train the new position quickly.

Have you tried him as an AMC? Is he effective? Give it a go for 3-4 games, esp against weaker opponents. If he cant perform against weaker opponents then there is no use using him as an AMC when he is best used on the left side.

Sometimes, if he performs as an AMC, then there is no need to even train him in a new pos. Just stick him in there.

Like some have said, some ST perform better as an AMC. They usually score a lot more in a deeper role.