i just put on new rear leaf shackles on the back of my 49 Chevy 1/2 ton PU and it made a world difference. I have 3 inch lower blocks but would like it to be about 3 inch lower yet. Has anyone every moved the rear spring holders up into the frame. I know I would have to box it out and re-enforce the area but it looks like I could gain about 3" Would this cause and unforeseen problems.

Mark