Cab/bed swap?

[modeler]

Hi all,

New guy here from Oregon, not sure if this belongs in this section...  Mods, if it belongs somewhere else please move it ;-)

I have a 1977 K20 that is in great mechanical shape. It has a crate 350 with 98k~ miles, a 4-speed transmission (SM465?), NP 205 t-case, factory axles, factory height. The engine runs great and is strong, it'll pull my 3,000 boat up all the hills between here and the coast in 4th gear. The transmission is tight, synchro's are in good shape, mechanically it's great!

As for the body...  It's beat to heck (if I can't use that term let me know)

There's a hole in the floorboard next to the driver's seat, the passenger side door only partly closes, the door striker bolts are (poorly) welded in place in rusty sheetmetal, there's a hole in the roof, the fenders are rusted out down low, the bed is bent and dented in every place, the tailgate is missing, etc...

My question is: How hard would it be to do a cab/bed swap on this truck? There's no AC, so no worries dealing with that. How long would it take a reasonably competent shadetree mechanic? I've done a few engine swaps on compact trucks and transmissions on older front wheel drive cars, I do most of my own maintenance anyhow. My work schedule allows me 4 days off at a stretch, is it possible for a guy to accomplish this swap in that time with occasional help from a friend? What is the best way to get the cab and bed on and off? I don't own anything capable of doing the lifting...

Looking to do this swap in late summer/early fall; doing the planning now.

Thanks!

[zieg85]

Easy enough.  Start looking for a donor truck.  Best to find a stick shift truck for the floor height needed, 4 wheel drive bump out and all can be cut out of existing cab if needed.  New cab mounts, and bolts.  Easy peesy.

[modeler]

Easy enough.  Start looking for a donor truck.  Best to find a stick shift truck for the floor height needed, 4 wheel drive bump out and all can be cut out of existing cab if needed.  New cab mounts, and bolts.  Easy peesy.

Other than the hole for the shifter, is the floor on a manual 4wd different than the floor on an automatic 4wd?

[zieg85]

Easy enough.  Start looking for a donor truck.  Best to find a stick shift truck for the floor height needed, 4 wheel drive bump out and all can be cut out of existing cab if needed.  New cab mounts, and bolts.  Easy peesy.

Other than the hole for the shifter, is the floor on a manual 4wd different than the floor on an automatic 4wd?

Being a 77 it probably bolts on, so the only difference is the hole I think.  Go to the tech section, there is a thread that shows the transmission hump pictures. http://forum.73-87chevytrucks.com/smforum/index.php/topic,25239.0.html 

[modeler]

Being a 77 it probably bolts on, so the only difference is the hole I think.  Go to the tech section, there is a thread that shows the transmission hump pictures. http://forum.73-87chevytrucks.com/smforum/index.php/topic,25239.0.html

That's a pretty good link. Given the general rusty condition of the cab and fenders, I don't think I'd be able to salvage the tranny hump out of my current cab, although I could be wrong. I'll have to take a look.

In the mean time, I'll have to look for a 4wd cab and bed.

[modeler]

A couple more questions:

1. I see that the cab bushing sets change between 1980 and 1981; does that mean the two cabs aren't interchangeable? Would I have to get a 1973-80 cab for my 1977 frame?

2. If I end up with an automatic cab/steering column will I be able to put my manual (shifterless) steering column in the automatic cab?

[zieg85]

Cabs are interchangeable,  Bushing are specific to the frame.  81 and up cabs have different hood hinge set up, there is another thread on the differences.   All the pedals and steering columns all interchange, subtle differences in the 84 on up dashes/dash bezels due to the wiper/dimmer switch is integrated into the steering column.

[modeler]

Cabs are interchangeable,  Bushing are specific to the frame.  81 and up cabs have different hood hinge set up, there is another thread on the differences.   All the pedals and steering columns all interchange, subtle differences in the 84 on up dashes/dash bezels due to the wiper/dimmer switch is integrated into the steering column.

Cool. So this '81 1/2 ton auto cab I'm looking at will fit on my '77 3/4 ton frame with '73-'80 bushings?

[zieg85]

Cabs are interchangeable,  Bushing are specific to the frame.  81 and up cabs have different hood hinge set up, there is another thread on the differences.   All the pedals and steering columns all interchange, subtle differences in the 84 on up dashes/dash bezels due to the wiper/dimmer switch is integrated into the steering column.

Cool. So this '81 1/2 ton auto cab I'm looking at will fit on my '77 3/4 ton frame with '73-'80 bushings?

Yes it will

[blazing816]

Just make sure you have a few guys to help lift the cab off and on....do not really think that one man can lift that off...lol. That is unless you have a hydraulic lift.