Tire Position Problems

Did you check if the leafspring pack still has the center bolt in it?
If it's gone that might be the problem.

Like mentioned earlier, you could also slot the hole in the axle's shockplate and springperch, so you can move the axle forward slightly.

Maybe if you loosen the U-joint nuts just a bit and wack the rear of the springperch a couple of times with a large hammer, it might be just enough to gain the little room you need.