leaf spring mount

I have a 1962 Pontiac Acadian . i am presently replacing all the passenger and trunk floors . I have a 9' Ford rear end which i will be shortening to fit under my car , i am doing a mini tube and leaving the frame rails in the original position. My question is currently i have a stock mono...

Moving leaf spring mounts on 66 Can you move the front and rear leaf spring mounts inward, narrow the rearend and widen the inner wheel wheels to make room for wider tires on a 66. Would I want to? How close together can you put leaf springs so they will still do their job correctly?