How much money do you have available?
Do you have a place to perform the needed work?
Do you have the tools that will be necessary?
Do you have the paitence it will require?
Do you have good neighbors?
Do you have any mechanical experience?
If the answer to more than two of these question is NO then you will probably be better off buying something that already runs and is safe. Leave the old truck project until a later time when you have some extra time and money. There will always be time later. Focus on school now and the other items will fall into place.