Raising just the back requires either moving the bottom of the door back or the top hinge point forward. You have to remove the upper and lower panels on the door interior to get at the bolts. It'll change the gap on the door at various places, so you have to watch for that.
You may just need to adjust the striker on the body. Before you move the door, be sure that it really needs it. If the molding matches with the body at the back, don't mess with the door position. That's where it needs to be.
