Swapping a 2.8L with a 3.1L?

I may also have a line of getting a 3.1 L engine instead of a 2.8L....I know that they are basically the same engine, except for piston size...so would I be able to drop the 3.1 in, or would I be into a nightmare of changing wiring harnesses, sensors, and computer modules?

I tried to use the search function to find any relevant posts, but I must not be putting in the correct words for could get nothing to show up....sorry to all if this is a repeat question.

The 3.1 and 2.8 are the same engine except for the stroke on the 3.1 is longer. They changed the stroke for better balance to keep the lower end in them longer. All the sensors are the same in both engines. Even the fuel rails can be swaped between engines. I do not know if the heads can be or not. The only catch is that it has to be close to the same year, 88 to 91 otherwise you have to change motor mount points.