Most likely they do, but I'm not sure. You will also probably loose the overload leaf. How long are they? If they are shorter than the lower leaf (not the overload leaf) then yes. The Deaver progressive 3 leaf ons do. I just posted a write up on that install on my site
place them on top of the overload spring(s) . you will need to replace the old center pin for the new longer center pin in the main leaf assembly. you should have received instructions, read them before you get yourself into trouble.