We've done a couple, a VW bug and an S10. Some people use some sort of stock hinges and modify them and some buy hinges made for this purpose, that is what we have done. Suicide Doors makes some nice hinge kits that are never simply a bolt on, but that can be modified to work well.
The key is to get the rear section of the door jam strong enough to support the door. Normally the car builders make the front of the jam strong enough to do that job, but the back only acts as a latch point. We used box tubing to build in inner structure to reinforce this area and also give us a bolting spot for the new hinges to go.
Another consideration is that you have to find perfect locations for the hinges so that they are in the same plane. If you are off they will bind and not swing right or the door will sag when opened. We got the top hinge temporarily positioned then ran a round rod through it and positioned the bottom hinge in the same plane. Even at that you have to play around to make sure you have chosen the right spots. We actually took the time to build a jig to position the two hinges identical on both sides of the car.
For latches we used Bear Claws and also used the sliding safety bolts as an extra measure of securing the doors when underway. They didn't get the name "suicide doors" without good reason!!!
Lastly, you will want to cosmetically dress up both front and rear jams to look like they were intended to be like that. You will need to fill in the old hinge pockets in the front and create a new latch pocket. In the rear you will need to fill in the latch pocket and create new hinge pockets.
Gotta tell you it is a very time consuming job to do it right. You are essentially reengineering the entire car door system and need to check and recheck clearances and fit as you go.
Don