Confused newbee with a 273

Thanks for the heads up on the etiquette. (I guess I'm a lazy typer???) I believe the headers are 1 5/8, so that'll work for the final Magnum package for my 'Barracuda'.

I'm looking for the mods that I can do now that will stick with me through the final package. If the headers fit, I'm absolutely good with doing them, the "X" pipe & duals. No performance gain on the 273 with headers, but it'd be a step in the right direction with a little more desirable tone coming out the back vs. the single on it now.