Originally Posted by TheStig88
The newer 2.3 will fit okay; like Pops suggested, you might consider installing a 5.0, which is a (relatively) easy engine swap. If you want to stay with the four-banger, but want a little more power, you might consider adding a turbo to the 2.3. That is another comparatively easy installation, using the engine (or just the turbo parts) from a T-Bird Turbo Coupe, a Mustang SVO, or a Merkur with the factory 2.3 turbocharged engine. The later 2.5 liter Lima engines which came with the Rangers until early 2001, can also take the turbo, and they offer a little more torque to the game.
Get out your tools, and good luck!