well there are 2 versions. I guess we are talking about for the OS 1.60 1 that jerry smith builds which is longer with a smaller diameter can. Works well. I don't know the dimentions of it.

The longer one that he builds and sell is quieter than the short one that I have.
But I bought one fromone of his friends. and it runs great. Pressure fitting is a 6-32 tapped in the header.
2"diameter x 10" Long hair spray can.
Inlet is the back 2" of header JB welded into the can.
stinger is 1/2 I.D. Inside diameter Aluminun tubing. Length of it it is about 1-1/2"