Exhaust manifold swap - need help to solve a gap

[msg]

My new L31 vortec hasnt been broke in and I have decided to swap out the headers with ram style manifolds. The distance between the new flange and the existing exhaust needs to be connected somehow now be it temporary or longer lasting just so I can break in the engine in the garage by revving up to 2000 rpm for 20 min or so and swap out the oil and filter and then take to a shop to fabricate whats needed. Anyone have advice on what I should do here?

Here are pics of the headers and the new manifold. The tape line shows about the length of connection I need.