Leaf Spring Relocation Kit
Also, here's some more pictures of the early bumper modification to clarify what I said. Here's what a '74 with a rear shock bumper looks like at the rear panel
You can see the large "D" shaped holes for the shock mounts
Here's an earlier rear panel. This one's a demon, but it doesn't matter.
The smaller outer holes are actually the ones you need for the early bumper brackets. The outer one is actually still behind the outer panel on the later cars
So you can drill that one out and use it to locate the other hole. The problem is it falls into the middle of the "D" shaped hole on the later shock mount bumper cars. That's where I made the bracket, but what I should have done was just make a "D" shaped patch out of 16 gauge metal and weld it in.
Here you can see how the bolt for the early bumper bracket falls into the middle of the "D" shaped hole, and the bracket I made. But if you just weld up the hole you wouldn't need the bracket. Or you could just use an "L" bracket and weld it to the end of the frame rail to make the mount stronger, like if you wanted to actually use a bumper jack.
I'm kinda surprised I haven't seen this brought up before, apparently not a lot of folks do the 3" relocation on shock mount bumper cars.
Here's another way, YoungGun2.0 used spring sliders. He recessed his up into the frame, but I don't think that would be necessary. You should be able to keep the car at about the same ride height if you just mounted the sliders to the bottom of the frame rail. He moved his up a little to lower the car. His is post #7.
Rear Leaf Relocation Kit pics
This is how he did it
But I think this would work just fine, you'd just have to figure out how to weld a few nuts into the frame to bolt the bracket to. Or weld the slider to the frame rail, but then it's a little harder to remove it later. If you did this, you'd just have to buy the spring sliders instead of converting the entire rear bumper because you should be able to leave the shock mounts in place.
The car would be lowered a little less than 3/8" with them mounted like this ( I used spring sliders bolted to the bottom of the frame of my car, but at the 1/2" relocation mark not under the frame rail).
Also, here's some more pictures of the early bumper modification to clarify what I said. Here's what a '74 with a rear shock bumper looks like at the rear panel
You can see the large "D" shaped holes for the shock mounts
Here's an earlier rear panel. This one's a demon, but it doesn't matter.
The smaller outer holes are actually the ones you need for the early bumper brackets. The outer one is actually still behind the outer panel on the later cars
So you can drill that one out and use it to locate the other hole. The problem is it falls into the middle of the "D" shaped hole on the later shock mount bumper cars. That's where I made the bracket, but what I should have done was just make a "D" shaped patch out of 16 gauge metal and weld it in.
Here you can see how the bolt for the early bumper bracket falls into the middle of the "D" shaped hole, and the bracket I made. But if you just weld up the hole you wouldn't need the bracket. Or you could just use an "L" bracket and weld it to the end of the frame rail to make the mount stronger, like if you wanted to actually use a bumper jack.
I'm kinda surprised I haven't seen this brought up before, apparently not a lot of folks do the 3" relocation on shock mount bumper cars.
Here's another way, YoungGun2.0 used spring sliders. He recessed his up into the frame, but I don't think that would be necessary. You should be able to keep the car at about the same ride height if you just mounted the sliders to the bottom of the frame rail. He moved his up a little to lower the car. His is post #7.
Rear Leaf Relocation Kit pics
This is how he did it
But I think this would work just fine, you'd just have to figure out how to weld a few nuts into the frame to bolt the bracket to. Or weld the slider to the frame rail, but then it's a little harder to remove it later. If you did this, you'd just have to buy the spring sliders instead of converting the entire rear bumper because you should be able to leave the shock mounts in place.
The car would be lowered a little less than 3/8" with them mounted like this ( I used spring sliders bolted to the bottom of the frame of my car, but at the 1/2" relocation mark not under the frame rail).