And/or worth it to put a 2002 Malibu 3.1L V6 into a 1998 Malibu? There is currently a 3.1L V6 in the 1998, but the Manifold Leak caused the heads to become warped, and we have come across a 2002 3.1 that has been rebuilt for less than it will cost to repair the current motor, we just don't know if it is possible, or worth the time and effort, to try to put the 02 into the 98 body. Any suggestions/ideas welcome!

Sure you can, same chassis etc. Should drop right in. As for as if it is worth it. That depends on alot of things, namely the cost of the swap and the condition of the car it is going in.

Any idea how much modification we'll have to do to attach the transmission and all the hoses and stuff? Thats the main thing we're worried about, that it's going to be a huge pain in the rear to get it functioning once we drop it in.

And the 98 is in truly excellent condition, the only problem we have had is that manifold leak, and it got to the point of severe overheating, which warped the heads.

Any idea how much modification we'll have to do to attach the transmission and all the hoses and stuff? Thats the main thing we're worried about, that it's going to be a huge pain in the rear to get it functioning once we drop it in.

And the 98 is in truly excellent condition, the only problem we have had is that manifold leak, and it got to the point of severe overheating, which warped the heads.

Then why not just swap the heads?

The 3.1 should just go in with no modifications. If you are going to do a swap look into putting in a 3.4L, same block, I believe it just drops in also. Just would be a different PCM. Worth looking into. GM didn't change much, if not anything, on the 3.1L throughout the years it was used.