If I use boomerang shackles when I do the ruf swap do I need to change my steering

 

It's a 83 4x4 truck

 

One of the advantages of the ruf is that the rear springs have an offset center pin, which pushes the axle forward about 3".

Are you planning on switching to high steer any time?

Boomerang shackles dont have anything to do with it, its springs you choose.

 

I am doing 63in rears and what a small lift up front without high steer