Mine is pretty similar to yours boucher but I couldn't run mine below the frame rail.

Because I'm a boss and amazing at everything, I worked for about 4 hours today getting the manifold bolts converted to studs, getting the new manifolds put together and put on, and getting most of the uppipe put together. My buddy kept stressing to me to try that pipe I already made but I was reluctant since I knew it was too tall. So All i really needed to do was cut off a bit on the top to make it a little shorter and then it fit just fine. All I have left to do is final weld and put the flange on. I have had the flange on and the turbo positioned and it fits fine but my tack was very weak and it fell off.

Here it is tacked together.


Decent amount of clearance between it and the frame


Pic of it out of the car


I ran into a pretty big problem putting the manifolds going together. The "heat riser" (I guess it'd be called?) hit the 292 manifold in a few places on the 1st and 2nd/3rd runners.
Mainly on the 2/3 runner


But I ground it down and it seems to have sealed well


Then another problem is that the manifolds weren't flat at all. I hope they straightened out after being torqued down but the 4/5 exhaust manifold runner was too far back about 1/8"

69 Buick Special Deluxe. Intercooled Turbo Chevy 250 @ 15psi on a stock long block. It's kinda fast.