I have been wanting to do this to this truck since I bought it in 1993. Finally got around to it last year. Plan was to extend the cab 2' by lengthening the frame 1' and shortening the bed 1'.
First step was to lengthen the frame. I did the job with it on the wheels rather than teetering on jack stands alone. Careful measuring for square, levelness, etc. is of course required before making the first cut. Photos 1 & 2 show the finished extension. I used some rectangular tubing that was a perfect slide on fit for the frame rails. I boxed the rails for 6" on either side of the cut. Once cut, I slipped the tubes on (note the spear shaped ends on the tubes. This avoids any vertical welds that may induce a stress riser and crack. I welded everything with a Lincoln buzz box about 90 amps w/ 1/8" 6011 rod. Note the 4" round holes I plasma cut for access to wiring, brake and fuel lines to be run inside rails.
(click photo to enlarge)
| 
(click photo to enlarge)
|
|
|
)
)
)
)
)
)
)
)
)
)
)
)
)
)