94' rear-end in to and 86?...

Can it be done? My freind has a 94' Formula 6 speed with the 3.42 rear-end. My other friend with an 86' T/A wants to swap it out onto his. He currently has Drum brakes while the newer one has disc. obviously... Well, has anyone heard of this being done. I know that the newer rear-end are slightly longer than the older ones. We are not worried about the brakes we are gonna swap everthing over to convert him to 4 wheel disc. So the main concern is, can it work. We were just gonna go for it one day but I thought I would see what u guys thought on this or if u have heard anything. Thanks.