Exh manifolds in an Early A...
340 manifold on early abody is not a good combo. Binds up at steering column.
Never modified one but the factory early a- exhaust manifold for drivers side is the best route. But very restrictive for anything but a 273 stock motor. People use it all the time but I’m just saying it could be better.
I used the 2.50” tti exhaust for the stock manifolds (273) and duals making the needed mods to the transmission mount. I’ll see if I can add pictures.