FINALLY!
Z is back in the garage and on the lift. Got the Sikky headers in without too much fuss, they went in from the top and the only thing I had to do was remove the PS pump and disconnect the steering shaft to get the drivers side in but that's no big deal.
The V-band flange surface on the headers end up angled at 60* so a 30* bend would be perfect, alas I only got 45's so I did an angled cut and got one side tacked up to the pre-fab X pipe. It's a little late now but the prefab is 409 stainless so I may just get the mid pipe cerakoated.
I mocked up the rear muffler just to have a sit and stare to figure out how to achieve what I want to with it. The magnaflow I chose has a 22" body so it's pretty wide and I may need to do a ton of pie cuts but that's speculation at this point. Side note I think I need to change the axle seals.