Here's a nice and safe way to get the springs in and out without wrestling with a universal spring compressor.

I fabricated a tool that fits up through the A-arm and spring into the 'key' slot up in the K member. The 'key' part is a T cut from 3/8" plate with a threaded rod welded to the bottom of the T. The T goes up into the K member, turns 1/4 turn, then sits down into the K-member formed recess.
I used a fine thread rod and greased it up for less friction.

I imagine this is how the factory does it. The threaded rod extends down through the A-arm spring pocket and through a flat plate (5x5").
Just tighten it up to compress the spring, remove A-arm bolts (use an air chisel if they are stuck), then back off the nut on the threaded rod. Works perfectly, and is SAFE! Allowed me to beat out the bolts that were a bitch to get out without having a jack in the way. Reverse to reinstall.

Here's the pics.





I should have made the threaded rod an inch or 2 longer...so 16 to 17" long overall.
You can see how it fits into the K-member.
Spring can't get away with the rod through the middle.

Also posted here: Post #47
https://www.thirdgen.org/forums/susp...ion-101-a.html

 

Here is a link to another method using an internal spring compressor:

https://www.thirdgen.org/forums/susp...y-install.html

 

While the idea has merit and with some refinement probably a realistic option, right now it looks sketchy as F to me. Are we sure that small threaded rod is strong enough for this application considering other spring compressors use 5/8 or larger threads?

 

I used alloy rod (high strength 7/16”). It's good for more than 10,000lbs tensile. The top part made from plate is the weak part, but will still compress an iroc sping over 12" if you do the math.
Could always use 5/8 or 3/4" rod if you want..
I can see how it looks weak as you're right it's a lot smaller than a regular compressor..but they are also designed to take a lot of bending on the rod as they are always eccentrically loaded.

 

Use a T-bolt, and a Acme shaft. An Acme shaft/lead screw won't bind up like all-thread. A resourceful person could probably rob the parts needed from a scissor jack.