We should keep into consideration that not everyone believes in souls. As well, we should not speak of subjective matters with absolutes because that is fallacy at best.
Physically, a body can be pronounced dead for a small amount of time and be revived to the point where it functions again. Regardless of belief in a soul or the possibility of another inhabiting it, the physical brain will retain all of the previous memories it had if they are still intact and not damaged. At that point, you still wouldn't be able to tell if there is a soul, and even if you could, you wouldn't be able to tell if it was the one you were looking for.
If you hold belief in reincarnation and that people can "remember" their past lives, then you would have the belief that we can physically ascertain through psychic means the physical thoughts of another person that no longer exist. Given that belief, and the belief in a soul, it would be theoretically possible.
However, this gets into gray territory and is strictly belief. It also gets into territory where the likelihood of your desires being manifested are slim because many things would have to fall in line for it to even begin to work, let alone be successful.
Personally, I would not attempt this and urge anyone else not to because there is a very small window where a body is considered dead (legally around where I live, only doctors can pronounce a body dead, even if the person's life ended in an ambulence) and the body has not started decomposition. This is the time frame people in hospitals would be using to try and revive someone and to be caught up in a situation where you'd have any amount of opportunity to work could mean you can legally get into trouble if you were found to be involved in the death of another person.