Leon, Welcome to our world! If you read through this thread you will see some ideas for manifolds. Remembering that the 153 is 2/3 of a 230 six and has the same port spacing just with two of the middle ports gone. The exhaust is the same spacing as the small block V8 with slightly larger ports. So any 3 carb manifold for 194-292 sixes is an easy modification. I can not believe that mine is the only one I've ever seen. They may be out there. I have heard of V8 tube headers being used but not a cast one. 4 cylinder headers do show up on eBay sometimes. Clifford made a 4BBL intake. Our own Scott Marshall(CNC-Dude) owns the pattersn and rights to the Duggan 4 and six cylinder engines. He is putting his foundry together now. He also has the ability and means to produce any cast aluminum part needed.
There are a couple of threads on the HAMB on these engines. There are some good pictures that may give you some ideas. Chevy II 4 Banger Chevy 153 Four Cylinder
"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
