The driver and passenger actuators are easy to access.
Loosen the two black screws above interior door handle pop out plastic piece behind door handle, use pry tool or flat screw driver (be careful) and undo plastic caps going around door from left corner down and back up to right corner. Slide door panel upward to loosen it from the window ledge, being careful to remove the window switch/ handle assembly from the panel. You can unclip the mirror adjust joystick and take the panel out completely or just let door panel dangle (being careful not to rip wire). Remove Window guide (1 bolt), make sure window is all the way up and closed, push down on guide and you can lay it down inside the door. Get a drill with drill bit and drill out the rivet holding the actuator (make sure you just drill out the rivet, and don't expand the hole). Actuator should be free to move around. The latch connecting to the handle assembly is hook shaped, you have to angle it in a way that sets it free (im pretty sure you move it right and upward). Remove the clip attaching actuator
Now this varies based on which actuator you got. The Dorman universal ones from Autozone come with all different hooks for any door you want to put it on for the explorer. If it is like this find the hook that matches the one you took out. Get the o-rings and the cap and funnel the cap through the road and place the rod in the actuator. I could never figure out how to secure the cap. I placed it standing up so connector was on table, got a pair of pliers, put it around the cap and hit it downward until the cap locked the road onto the actuator (make sure you have the o rings and stuff correct, the cap doesnt come off once you put it on). You are lucky if you got a specific driver side one already assembled
On the original, use pliers to take the u shaped piece of metal off it that connected the actuator to the door. You have to fit that piece of metal onto the new one (unless yours already comes with it on). Mine came with a bolt and nut to use in place of the old rivet. Place the bolt through the old rivet hole on the metal u shape piece so when re assembling, the threads are facing you and the head of nut is facing the actuator. get one side in the hole, then use pliers to bend it onto the other side (be careful you can get cut). fish the connector through the hole for door assembly, attach electrical connector and fit it into orignal place, keeping finger on head of bolt and making sure threads go through hole on the actual door. Screw on nut. you need a small wrench to put on the head of the bolt and a ratchet on the nut to screw it in. Screw in tight, but too much will cause the metal to bend or nut to go through the metal and you will need a washer then. Test to make sue door lock fires up and down. Put window guide back in place. You are supposed to use new plastic clips but I reused the old ones and no problem. put clips on door panel side, reattach window switch assembly to panel, going from top slide panel into window ledge and through lock hole then push door panel in so plastic clips lock in, attach plastic behind door handle. screw in two black screws. Done.
Also, I sprayed the actuator and whole mechanism with spray lithium greese to keep moisture and debris out of it.