I don't see anything about it in the FSM, it only seems to go into removing the springs. What do I need to do to make sure the springs are unloaded, so I can replace the front & rear bushings without killing myself? I'm guessing it's not OK to just go at them with the truck sitting on the floor of the garage, right?

The manual mentions lifting the body of the truck up, then jacking the axle up until there's not load on the spring or something like that. I sure don't have a jack big enough to even reach the frame, much less reach it then be able to lift it up high...any advice, or is this one of those things I need to either get more tools, or take it to the shop for?

 

Yes you need a good (=big) set of jackstands under the frame. take the tires off and put a jack under the axle. Droop the suspension out all the way and then jack up the axle just a little so there is no tension on the spring bolts. You will probably have to cut or torch the bushing or bolt out so be prepared and be careful you dont drop the axle on yourself

 

I jacked mine up then put jack stands under the low part of the frame in front of the leaf springs. My jack stands weren't tall enough, so I put 2x4's together to make spacers for the jack stands until they were tall enough. Now in my case the bed was off so the bulk of the weight was in the front anyway, so I had no balance issues by only having support in the front and middle of the cab, but I am not sure if the bed would add enough weight to cause the truck to tip backwards if it were only supported in the middle. I sort of doubt it would , but I am not certain. You could perhaps try my approach, and make jack stands for the rear just to prevent tipping. You could use spare lumber, basically just to brace it up. I am sure someone will have a better idea, but this is one thought for you. Good luck.
My biggest obstacle so far has been getting the connecting bolts out of the bushings. I have tried lube and heat, in combination with a 3 pound sledge. It does work, but the force required seems excessive, plus I am quite strong, I have a tendency to break things when I use that kind of force.
My grandpa used to say I could tear up an anvil in a sand box. that of course is a little bit of and exaggeration, I would have to have a few other tools too, but a sand box is a good start. LOL

 

You can put a jack under the axle and lift that up high enough to get jack stands under the frame. Then remove the tires and lower the axle down until it is at full droop. I raised my jack stands (the tallest ones Harbor Freight sells) with 2 pair of 2x4s laid up in in an overlapping square pattern (adds ~3" of height and makes a more stable base):

 

Alright, thanks a lot. I'll see if I can work something out with what I've got in my garage. Otherwise, it'll go on the checklist of things to have checked out/worked on by a shop once it's up & running again.

 

Not too bad to do.

We bought 6 ton jack stands (taller than those little 3 ton ones)

Set frame on stands, let axle droop, use jack at the spring under axle to get to a neutral load. The fronts were easy. Change one end at a time. Start spraying PB blaster on the threads a few days (multiple times) before starting the job.

We had to cut off the bolt at the front of the rear springs. Both sides siezed into the stock spring bushing steel sleeve. If your new bushing has steel sleeves, put anti-sieze on during re-assy.

 

Thanks! I've put it off for now...more important things to do, but I've got the bushings and I'll get around to it at some point.