ok im in the middle of doing a sas on a 94 ext cab pick up , i have a 3 inch trail gear lift and i have the axle under the truck all bolted up and it seems way to far forward. something seems off , the truck is on its own wieght to, sorry for the bad pics .

 

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The shots might be kind of deceptive....raise the rear up as high as it will be in real life and take another look at the profile of the tire. I know you have to have it favoring the front of the wheelwell due to the rearward shackle and the tire travels rearward during compression. I have the opposite situation because my shackle is on the front of the frame horns. My wheel travels FORWARD during compression.

 

Looks about right to me. As Zuk said, then the suspension compresses the axle will move toward the rear since the shackles are in the rear.

Here is my truck using the 3" TG kit. You can see the shock/hoop is at an angle as well accounting for the rearward travel of the axle.