You will NOT be able to swap a Ranger chassis for the Explorer chassis without a TON of work to either the chassis or the Explorer body.
A couple of immediate differences:
The Ranger kicks up behind the cab -- a lot compared to the Explorer frame that drops down instead.
The Ranger fuel tank will also hit the Explorer floor boards.
The Ranger is sprung over in the rear -- which is absorbed by the kick up in the frame rails behind the cab, so you don't get an immediate 5.5" lift like it seems -- it will still ride flat.
Now, that being said, the Ranger frame is better for off-road work BECAUSE of the kick up in the rear part of the frame. The Explorer is constantly hanging up on the front brackets of the rear leaf springs where they are mounted to the frame. The Ranger frame won't have that issue.
Here are a few pics of my Ranger build in process. I'm installing an extended cab onto a regular cab (86) long-bed frame. You can see how the rear of the frame kicks upward at the rear of the cab. (Note that I am forced to remove the stock fuel tank and also to either channel the floor of the extended cab or raise the front body mounts by about 3" to make the extended cab fit on a regular Ranger frame!)
(lost photo)
Here, is a shot of my Sploder -- note that the frame for the Explorer rides flat under the body, kicking up some after the front spring hangers and then going straight back to the end of the frame.
(lost photo)
If you really wanted to run the Ranger frame, it could be done. You would have to loose the rear seat, channel the body over the frame rails, and use some alternate fuel tank.
