I HAVE A 81 F150 2 WHEEL DRIVE AND A 83 F150 4 WHEEL DRIVE. THE 4 WHEEL DRIVE HAS A RUSTY BODY AND I WAS WANTING TO SWAP THE RUNNING GEAR OVER TO THE 2 WHEEL DRIVE. I WOULD LIKE TO KNOW IF THE FRAME IS THE SAME ON BOTH TRUCKS? I THINK CHANGING THE RUNNING GEAR WOULD BE EASIER THAN SWAPPING THE BODY. ANY HELP WOULD BE GREATLY APPRECIATED.  

i was reading something like this ???  

Shouldn't be too difficult as long as you have all the parts in front of you.

My only concern would be the front suspension mounting points, be sure to check them over closely before doing anything, if they are the same then go for it!  

If you have a donor truck it should not be that bad to do but if I was going to go through the trouble to convert it to 4x4 drive, I would not install a TTB front drive axle and would do a solid axle conversion from the get go as it would be same work or less and yield a far superior setup too.  

I agree with Sno, I would SAS it...

My concern with the swap, as evidenced above, is the mounting points for the TTB vs. the TIB. I know for a fact that on the Ranger that TTB and TIB mounts were different so swapping from a 2-4wd is not an easy task. The F1's I don't know about though...

You know, I just noticed the the OP posted this back in '06... bet the swap is long been done... wonder what happened? lol  

I noticed the date but sometimes people read the old posts looking for new ideas and it does not hurt to "freshen" them a bit as needed on such subjects.