Reply to "180 degree header question."

I've got the exact same headers, although I have not trial fitted them yet. I bought them off someone here who had pulled them from a pantera stash of parts. They are the SVO/Yates exhaust port for a cleveland (9.2 deck). You will need to do a little more digging on your motor to find out if its a windsor 9.2 or aftermarket 9.5 deck block or a cleveland block with yates heads? May explain the need for the block spacer. The spacer could be the result of a 9.5 deck block and yes the open spacer does negate the bundle of snake separated pulses. My understanding is the headers were commissioned and sold by Hall and built by Stan's Headers here in WA State for Hall.

If you don't mind can you produce a video of what your car sounds like and dump it on youtube, I'm interested to get an idea of what I would get with this setup. I'll produce some mock up pictures in a few days. It shouldn't be difficult to draw a template with the 4 holes and have it CNC'd correctly to replace the current spacer. I'll let you know if it lines up correctly on my cleveland block with c302 heads without the spacer.