W;
I'm not familar with what Brazil has/does.
Headers aid in 'exhaust relief' at speeds at/or above 4,000 RPM and why there used on Hot Rods. Operation(s) below that don't require, any "extra relief" is all.
The question stated, he was going to use a single pipe, wasn't going to haul/tow this "driver" and didn't know where to go.
Under those specific needs; 'headers' are of no value, or any of that "extra plumbing" either..
The 292 manifold fits that set of circumstances (unloaded-low RPM) at a low cost, if some "extra relief" were wanted.
Happy trails.
