73 Duster Restoration

Yeah, really nice!
As far as the exhaust, those are two chamber mufflers, so I'm not sure if the Thrush will buy you much in terms of sound. I'd ditch that stupid X pipe before changing the mufflers. But in addition to the better sound of headers, you will be replacing those home made 1 7/8 headpipes I made. So you will gain twice there. It's a shame that Pypes system sucks as bad as it does. It looks decent before you realize it won't fit, and the price is unbeatable. After that fiasco, I swore I'd never do an aftermarket exhaust again, and I stuck to it. I just put the JCW sound kit on my Cooper, and it's sweet. But that's what $1,100 buys you (didn't pay that much). Plus it's one piece, as a factory exhaust (that doesn't go over an axle) should be. Just put it on the hangers, and go.