well.. i have some fiberglass doors (skins) on the way.. but i still havent totally figured out what i am going to do for a latch. What seems to be the best way that can be opened from the inside and outside. its on an 85 crx if it makes any difference. *race use only*

 

my doors have a small t handle that when is pushed down it unlatches the door.

i also have them things that mount into the top of the window and they clip onto the "rail on the body of the car" to keep the windows in the car.

 

my MB doors can use the stock latches.

 

For the top, most people are using "Pro-Stock Window latches" to keep the top of the door from pushing out at 100+mph. Those run around $60 EACH. I'm working on a much more simple (and less expensive) setup on our all-motor civic and corrado 'glass doors.

For the actually door latches, we use the stock honda and vw latch and striker. On the inside, we have a simple pull cable. On the outside, I used an old Gm style door lock button (think of a golf tee). there is a little hole drilled downward through door, right below the rear bottom corner of the window. The 'bottom' screws onto a thin rod, which goes through the hole and to the latch. pushing down opens releases the latch.

We went with this setup, because it was the cheapest, easiest, and does Not require any holes/opennings in the polycarbonate windows.

I'll see if I can find some pics later.

Oh a couple of other things.

At the top of the door frame, we use a strip of angle aluminum, to control how deep the top of the door seats
At the bottom rear corner, we have a "stopper" to put outward pressure on the door. When the door is latched, the stop pushed out on the door, so at the top, the door pushes in. The door sits nice and flush, but is good and tight too.

 

Here is a pic of my buddy Matt's car with the MB doors:


You can see how the latch system works. There is a hole in the window so you can open it from the outside.