Wheel size and back spacing

famous bob said
1" more offset, will move the wheel in 1" ! 1" wider wheel , will make another 1" toward the springs ! That`s 2": where I went to school ! Maybe were talking about offset to the inside, versus offset to the out side ???? I`m thinking offset to the inside . Just reread the OP`s first post, he did say from 4.5 to 5.5 , which would move the wheel toward the springs.

Back spacing is simply the dimension from wheel mounting surface to the innermost edge of the rim, adding 2" overall to a rim, but only adding 1" to the back spacing means
You've added 1" out, & 1" in,....which means the offset is the same...................................offset is how far from centered in the rim the mounting face is...................