early exhaust
I've done several early A exhaust systems on my cars. What I did is called tom Swoop at Accurate Ltd. They are located in Oregon. His guys are very knowledgeable and all they systems are fitted to actual chassis.
On my 64 Dart convertable i went with the Accurate Y pipe. i had to provide Tom with the part numbers to the manifolds. I purchased a Flowmaster two into one pipe which I installed at the end of the Y pipe. The straight pipe went back to the muffler and then we bent an over the axle pipe which went into the HP 273 resonantor. The muffler was a flowmaster. The exhaust sounded nice, no drone from the Flowmaster and from a performance standpoint the engine seems ed to respon well.
On my 64 Dart post car everything is the same except I have pipes from the fenderwell headers coming into the Flowmaster two into one with a straight pipe going all the way back to the resonator. It's not very loud and has a wicked muffled headers sound.