Stacking aluminum lowering block?

If you do a google search you will see guys who run 7s/8s in the qtr. on leaf springs with steel lowering blocks, a couple had blocks as much as 4". Opinions are kind of like the whole wheel spacer thing and you will see those guys running them as well at those times. I used these
LOWERING BLOCKS/pair (LB-01) – Calvert Racing, Inc.
as they can be stacked and are really good quality. I talked with calvert racing and ended up lowering mine 2" overall (my blocks are welded together) I have caltrac mono leafs and bars and have zero issues.