To be correct, the non catalyst models had an angled cap and the catalyst models had a vertuical one.

Most problems with 909 loads stemmed from the fact the early non catalyst ones are 2 piece (OE are as well) and the 909 ones were never fully pushed home, so the joint corroded quickly. Obviously if WE fitted them they are still fine. lol

The catalyst leads are 1 piece anyway, and thats what we fit here, to ALL cars if teh customer agres to a new cap.