Not sure what the dynacorn tub requires. I (my fabricator) cut the stock inner tub out and moved it over and added a 1 9/16" strip of sheetmetal in between. Thats about a 1/2" clearance to the leaf spring. I dont recommend doing this without adding a watts link if you are running low enough to be over the tire with quarter panel. Here are pics with the 315's. You can see how low I am in the rear and running hard in the corners causes the rear diff to shift side to side without a watts link in turn hitting the quarter panels.
