long bed trailing arm swap--Help!!--

[69gmcc10]

I have a 2wd 69 GMC C10 long bed that I am getting ready to convert from leafs to trailing arms and I had a few questions for you all. I have searched and searched and searched for answers on the forum and cant find what I am looking for so I am just going to ask some questions.

My first question is how to move the axle rear one inch so it is more centered in the rear fender? I have read posts that said people moved there rear axle back 1”, but I can’t find any pictures or info on how anyone did it. I was thinking of moving the cross member that the arms mount to back one inch by drilling new holes in the frame and bolting it in, but then the upper spring mount would be 1” further forward that the lower and I don’t know if I should be worried about that or not? I can always drill a new hole for that as well. I also thought this approach would eliminate any need to modify the rear drive shaft.

My next question is about the upper shock mount cross member, mine is not there, I have shock mounts on the frame where that bar should be, but no cross member. There is a similar cross member with a different lower support mount further forward where the leaf mounts to the frame, should I just relocate it to the further back location or look for the correct cross member? It does look a little bent, but my BFH can fix that, and I don’t need it to mount shocks because I am going for the shock relocation kit from No Limit, what do you all think?

My final question is that I don’t have the spring pad that is riveted to the bottom of the frame, is it necessary? Or can I just mount the spring to the frame?

Thank you all in advance for any help or suggestions you can think of.

[gringoloco]

I would grab the frame parts you need here on the parts forum. You will want the factory style shock crossmember and spring plates at the coil location- the shock crossmember not only mounts the shocks, but ties the rails together and prevents bowing and flexing. The entire weight of the truck will be riding on those areas and will need all the help it can get. The forward leaf crossmember is a completely different size/shape and would require a ton of work to make it not as good as stock...

Moving the center crossmember back is the way to go for centering the wheels- just drill and bolt in. I've also seen guys add a spacer between the brackets and the 'member. 1" shouldn't cause any alignment troubles with the coils- if anything, I think it may help realign things after lowering.

Depending on how low you wanna go, the Porterbuilt Stage 2 rear setup includes the doubler and shock crossmember as part of the kit.

Good luck! Stock parts make this swap bolt-in EASY