I have these manifolds on my 235 in my 51. 1-3/4 pipes mufflers under from edge of the bed. Both turned out behind rear tires. I used donut gaskets instead of the flat flange gaskets. On donut is a 2” double bevel and in is a 1-7/8 single bevel with a collar that inserts into the manifold. I couldn’t get the flat gaskets to seal.
