Hey all, I'm getting ready to purchase a 96 xlt longbed, but I am interested in what it'd take to mount a supercab to the frame (no body lifts, either). I know I'll probably have to chop into the cab a bit to make room for the frame. Other than that, what do I have to be worried about? The bed won't be a problem. Planning on a custom flatbed.
On pre '98, I think this is pretty easy as the cab mounts are riveted to the frame.
It is PIA to lift cab high enough to clear engine without a real hoist. (I did cab swap with gantry crane and engine hoist and things were just a little sketchy - doesn't help that my garage floor isn't perfectly flat/smooth or that I needed to remove wheels and have axles on dollies to have enough clearance).
Here's how I would do it:
Remove boxes from both trucks.
Loosen the cab bolts on both trucks. (ideally pull the mounts apart once as they are going to be rusted together) LMC has new mounts and would be ideal time to replace, but they are $$$.
Loosen/disconnect as much as possible before hand (electrical, steering, transmission, shifter, etc).
Push/pull/drag/drive the RCLB truck to your friendly u-wrench location/buddy with a lift. Bring 2nd vehicle & a trailer for cab.
Lift cab off, pull frame out; put trailer under and lower regular cab on to trailer to dispose of as desired.
Repeat with Supercab, but this time instead of trailer under, push RCLB frame under.
Bolt Supercab to frame with front 4 bolts, roll the frame onto dolly and tow home. (4 bolts keep cab from "falling off")
Back at home, undo bolts and lift cab so it sits an inch or 2 above existing mounts - exact distance isn't required, just that all 4 are same. (I thinking hockey pucks with a slot cut into them, so they can be slid in/out to verify mounts are all at same distance from cab, you can stack 2 or 3 high if required to keep cab from contacting frame in wrong location.)
Grind the rear RCLB rivets out of the existing mounts.
Position the mounts so that they are the exact same amount below the holes at back of cab as existing mount, clamp to frame and drill holes.
Bolt mounts into place, remove spacers and lower cab onto mounts.
Using something like pucks would allow measuring how much/where if at all you need to notch the cab floor to miss the frame rails.
Bolt cab in place.
Reconnect electrical, steering, transmission, shifter, etc.
Stand back and enjoy beverage. Then get to work on the flatbed.
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