I was wondering if anyone has done away the 4link suspension in favor of leaf springs. If so what degree of difficulty are we looking at?

 

I would suggest being very careful here.
When we alter a vehicle from the way it was built and certified , some insurance companies can walk right out from any responsibility for coverage in the event of any mishap. GM training warned us about this. Might pay to do a little homework and ask around.

 

Save that modification for the TV shows that have pros and a fully equipped shop with a unlimited budget.