Good Stock rear suspension shackles. They are good because all of the geometry is already figured out for you; just drive it.
Better Shackle flip.
The easiest way to get 4 inches of lift out of the rear of your 73-87 Chevy is to convert the rear to a compression style shackle. To do that you must flip the shackle so it is pointing down, instead of up like factory. It is entirely possible to do this yourself. You must get out the reciprocating saw and/or grinder and remove the metal below the factory shackle mount bolt so the shackle can swing. (1st 2nd and 3rd pics)
This makes clearance for the shackle to move forward and backwards, but leaves very little metal to support the rear of the leaf spring. I’ve heard of people running this way without problem…..but I don’t want to count on “probably”. You can fabricate your own supports and weld them in,
(pics 4, 5 and 6) but, as you can see, my welder wasn’t up to the task. Even if they were good welds, look at that compared to the 7th and 8th pics.
Best (This is my opinion) DIY4X Shackle flip n switch. Simply remove the old shackle brackets. I drilled the centers of the rivets out and popped them out with a chisel. You can use a cutting torch, or a hand grinder. I would recommend pulling the fuel tank (like I did) to make room for my big head and to eliminate any possibility of fire. I have heard you can just hinge the fuel tank down, but if you go that far, you might as well pull it all the way out.
Once the old brackets are out, the DIY4X kit is so complete, you just paint it your color of choice and bolt it in with the supplied grade 8 bolts. And look at how beefy they are! There is no question these will hold up longer than the rest of the truck. :jumps:
The only problem I had was hooking up my old shackles. (9th pic) All I did there was take some 3/8″x1 1/2″ steel and made up some 6″ (bolt to bolt) shackles. The stock shackles are 4″ (bolt to bolt) so this should give me 1 additional inch of lift. If it is too much I can just cut the shackles down and re-drill the lower hole.
That is that, now on to the rest of the truck.