TTI system questions

Here's what I ran into. If you assemble the system complete with headpipes starting at the rear, you can't raise the front up into place. The suspension is in the way. If you attach the headpipes to the manifolds then try to raise the rest of the system, you can't slip the headpipes into the h-pipe. The only success I had was doing the opposite of the instructions, starting from the front and working back.