[CC69Rat]

Just to add to what others have said..

If I have a 15" wheel. (Diameter) If I measured from the center of the wheel to the edges, it would be 7.5". (Radius) Not in any way assuming anyone doesn't know, just trying to help it make sense.

Thinking of it from a wheel Radius perspective vs. Diameter. If I add 2" dropped spindles to my truck, I am essentially changing the wheel radius. What used to be 7.5" is now 5.5" on the lower portion because the wheel centerline moved UP two inches compared to stock.

The clearance issues are introduced because of this 2" (Belltech for example) reduction, OR McGaughys makes a 2.5" dropped spindle. 2" is very tight on a 15" wheel, and even tighter if you have an 8" wheel with a lot of backspacing. 2.5" will rub, and I have had them even lock the wheel from rolling with a 15" rally wheel (depends on the backspacing)

They're really hard to find, but GM made a 15x7 Van rally that looks very very close to an 8" wheel from the outside. It doesn't have a lot of backspacing and works well with 2.5" dropped spindle. The 85 below is a 7" wheel, 2.5 spindle and 2" dropped spring. It works very nicely. Not the same truck in the pics. I borrowed the one showing the LCA clearance of the interwebz.

Hope this helps.