Bossho
Can you take some measurments to be sure ?
Pipe is 6 1/4" to base to collector.
Bolt holes the long way
8 1/2" out side holes
3 5/8 inside
The primary are 2 1/16" inside measurment
The collector its 2 7/16" inside measurment
The short way they are alll 2 1/4 "
I am think Its part # 121-170 for the f1000.
But only one way to be sure.