It could be a,

Coupe,

2 door sedan,

2 door hardtop,

2 door station wagon,

2 door roadster,

A bathroom door is 2 foot door or a 2 foot 4 inch door.

No they will not. Vehicles with 2 doors have longer doors than a 4 door vehicle to make up the difference in body panel length. A door from a 2 door standard cab s-10 will fit the front doors of a 4-door blazer but this is the only situation where a 2-door and a 4-door will interchange.

Yes.. a 4 door windshield will fit on a 2 door cavy.

Remove the door panel. Unscrew the door check bolts in the door jamb, 2 in the door and 2 on the car frame. Remove the check unit by pulling it through the door and out the door face. Install new check through the door and replace door panel.