It is confusing for sure...I just remember problems some had with a particular peirburg when installing the 65mm. You don't want to make a mistake with the 61 or 62mm for sure. I know I put out the part #, but I didn't purchased from Ebay. Not on something like this... Rob, supplied that pump. As stated above, right now I am fine. I even had Bryan look at the data when at the 1/2 mile event to get a second opinion. Don't skimp on this one, be sure if you buy used, you get the #'s correct. My coupe would flat fall on it's nose when it ran out of fuel, and I quit right there until I had the correct pump...